show.jl
# This file is a part of Julia. License is MIT: https://julialang.org/license
function show(io::IO, ::MIME"text/plain", u::UndefInitializer)
print(io, u, ": array initializer with undefined values")
end
# first a few multiline show functions for types defined before the MIME type:
show(io::IO, ::MIME"text/plain", r::AbstractRange) = show(io, r) # always use the compact form for printing ranges
function show(io::IO, ::MIME"text/plain", r::LinRange)
# show for LinRange, e.g.
# range(1, stop=3, length=7)
# 7-element LinRange{Float64}:
# 1.0,1.33333,1.66667,2.0,2.33333,2.66667,3.0
summary(io, r)
if !isempty(r)
println(io, ":")
print_range(io, r)
end
end
function show(io::IO, ::MIME"text/plain", f::Function)
ft = typeof(f)
mt = ft.name.mt
if isa(f, Core.IntrinsicFunction)
print(io, f)
id = Core.Intrinsics.bitcast(Int32, f)
print(io, " (intrinsic function #$id)")
elseif isa(f, Core.Builtin)
print(io, mt.name, " (built-in function)")
else
name = mt.name
isself = isdefined(ft.name.module, name) &&
ft == typeof(getfield(ft.name.module, name))
n = length(methods(f))
m = n==1 ? "method" : "methods"
sname = string(name)
ns = (isself || '#' in sname) ? sname : string("(::", ft, ")")
what = startswith(ns, '@') ? "macro" : "generic function"
print(io, ns, " (", what, " with $n $m)")
end
end
function show(io::IO, ::MIME"text/plain", iter::Union{KeySet,ValueIterator})
summary(io, iter)
isempty(iter) && return
print(io, ". ", isa(iter,KeySet) ? "Keys" : "Values", ":")
limit::Bool = get(io, :limit, false)
if limit
sz = displaysize(io)
rows, cols = sz[1] - 3, sz[2]
rows < 2 && (print(io, " …"); return)
cols < 4 && (cols = 4)
cols -= 2 # For prefix " "
rows -= 1 # For summary
else
rows = cols = typemax(Int)
end
for (i, v) in enumerate(iter)
print(io, "\n ")
i == rows < length(iter) && (print(io, "⋮"); break)
if limit
str = sprint(show, v, context=io, sizehint=0)
str = _truncate_at_width_or_chars(str, cols, "\r\n")
print(io, str)
else
show(io, v)
end
end
end
function show(io::IO, ::MIME"text/plain", t::AbstractDict{K,V}) where {K,V}
# show more descriptively, with one line per key/value pair
recur_io = IOContext(io, :SHOWN_SET => t)
limit::Bool = get(io, :limit, false)
if !haskey(io, :compact)
recur_io = IOContext(recur_io, :compact => true)
end
summary(io, t)
isempty(t) && return
print(io, ":")
show_circular(io, t) && return
if limit
sz = displaysize(io)
rows, cols = sz[1] - 3, sz[2]
rows < 2 && (print(io, " …"); return)
cols < 12 && (cols = 12) # Minimum widths of 2 for key, 4 for value
cols -= 6 # Subtract the widths of prefix " " separator " => "
rows -= 1 # Subtract the summary
# determine max key width to align the output, caching the strings
ks = Vector{String}(undef, min(rows, length(t)))
vs = Vector{String}(undef, min(rows, length(t)))
keylen = 0
vallen = 0
for (i, (k, v)) in enumerate(t)
i > rows && break
ks[i] = sprint(show, k, context=recur_io, sizehint=0)
vs[i] = sprint(show, v, context=recur_io, sizehint=0)
keylen = clamp(length(ks[i]), keylen, cols)
vallen = clamp(length(vs[i]), vallen, cols)
end
if keylen > max(div(cols, 2), cols - vallen)
keylen = max(cld(cols, 3), cols - vallen)
end
else
rows = cols = typemax(Int)
end
for (i, (k, v)) in enumerate(t)
print(io, "\n ")
if i == rows < length(t)
print(io, rpad("⋮", keylen), " => ⋮")
break
end
if limit
key = rpad(_truncate_at_width_or_chars(ks[i], keylen, "\r\n"), keylen)
else
key = sprint(show, k, context=recur_io, sizehint=0)
end
print(recur_io, key)
print(io, " => ")
if limit
val = _truncate_at_width_or_chars(vs[i], cols - keylen, "\r\n")
print(io, val)
else
show(recur_io, v)
end
end
end
function summary(io::IO, t::AbstractSet)
n = length(t)
showarg(io, t, true)
print(io, " with ", n, (n==1 ? " element" : " elements"))
end
function show(io::IO, ::MIME"text/plain", t::AbstractSet{T}) where T
# show more descriptively, with one line per value
recur_io = IOContext(io, :SHOWN_SET => t)
limit::Bool = get(io, :limit, false)
summary(io, t)
isempty(t) && return
print(io, ":")
show_circular(io, t) && return
if limit
sz = displaysize(io)
rows, cols = sz[1] - 3, sz[2]
rows < 2 && (print(io, " …"); return)
cols -= 2 # Subtract the width of prefix " "
cols < 4 && (cols = 4) # Minimum widths of 4 for value
rows -= 1 # Subtract the summary
else
rows = cols = typemax(Int)
end
for (i, v) in enumerate(t)
print(io, "\n ")
if i == rows < length(t)
print(io, rpad("⋮", 2))
break
end
if limit
str = sprint(show, v, context=recur_io, sizehint=0)
print(io, _truncate_at_width_or_chars(str, cols, "\r\n"))
else
show(recur_io, v)
end
end
end
function show(io::IO, ::MIME"text/plain", opt::JLOptions)
println(io, "JLOptions(")
fields = fieldnames(JLOptions)
nfields = length(fields)
for (i, f) in enumerate(fields)
v = getfield(opt, i)
if isa(v, Ptr{UInt8})
v = (v != C_NULL) ? unsafe_string(v) : ""
elseif isa(v, Ptr{Ptr{UInt8}})
v = unsafe_load_commands(v)
end
println(io, " ", f, " = ", repr(v), i < nfields ? "," : "")
end
print(io, ")")
end
function show(io::IO, ::MIME"text/plain", t::Task)
show(io, t)
if t.state === :failed
println(io)
showerror(io, CapturedException(t.result, t.backtrace))
end
end
print(io::IO, s::Symbol) = (write(io,s); nothing)
"""
IOContext
`IOContext` provides a mechanism for passing output configuration settings among [`show`](@ref) methods.
In short, it is an immutable dictionary that is a subclass of `IO`. It supports standard
dictionary operations such as [`getindex`](@ref), and can also be used as an I/O stream.
"""
struct IOContext{IO_t <: IO} <: AbstractPipe
io::IO_t
dict::ImmutableDict{Symbol, Any}
function IOContext{IO_t}(io::IO_t, dict::ImmutableDict{Symbol, Any}) where IO_t<:IO
@assert !(IO_t <: IOContext) "Cannot create `IOContext` from another `IOContext`."
return new(io, dict)
end
end
# (Note that TTY and TTYTerminal io types have a :color property.)
unwrapcontext(io::IO) = io, get(io,:color,false) ? ImmutableDict{Symbol,Any}(:color, true) : ImmutableDict{Symbol,Any}()
unwrapcontext(io::IOContext) = io.io, io.dict
function IOContext(io::IO, dict::ImmutableDict)
io0 = unwrapcontext(io)[1]
IOContext{typeof(io0)}(io0, dict)
end
convert(::Type{IOContext}, io::IO) = IOContext(unwrapcontext(io)...)
IOContext(io::IO) = convert(IOContext, io)
function IOContext(io::IO, KV::Pair)
io0, d = unwrapcontext(io)
IOContext(io0, ImmutableDict{Symbol,Any}(d, KV[1], KV[2]))
end
"""
IOContext(io::IO, context::IOContext)
Create an `IOContext` that wraps an alternate `IO` but inherits the properties of `context`.
"""
IOContext(io::IO, context::IO) = IOContext(unwrapcontext(io)[1], unwrapcontext(context)[2])
"""
IOContext(io::IO, KV::Pair...)
Create an `IOContext` that wraps a given stream, adding the specified `key=>value` pairs to
the properties of that stream (note that `io` can itself be an `IOContext`).
- use `(key => value) in io` to see if this particular combination is in the properties set
- use `get(io, key, default)` to retrieve the most recent value for a particular key
The following properties are in common use:
- `:compact`: Boolean specifying that small values should be printed more compactly, e.g.
that numbers should be printed with fewer digits. This is set when printing array
elements.
- `:limit`: Boolean specifying that containers should be truncated, e.g. showing `…` in
place of most elements.
- `:displaysize`: A `Tuple{Int,Int}` giving the size in rows and columns to use for text
output. This can be used to override the display size for called functions, but to
get the size of the screen use the `displaysize` function.
- `:typeinfo`: a `Type` characterizing the information already printed
concerning the type of the object about to be displayed. This is mainly useful when
displaying a collection of objects of the same type, so that redundant type information
can be avoided (e.g. `[Float16(0)]` can be shown as "Float16[0.0]" instead
of "Float16[Float16(0.0)]" : while displaying the elements of the array, the `:typeinfo`
property will be set to `Float16`).
- `:color`: Boolean specifying whether ANSI color/escape codes are supported/expected.
By default, this is determined by whether `io` is a compatible terminal and by any
`--color` command-line flag when `julia` was launched.
# Examples
```jldoctest
julia> io = IOBuffer();
julia> printstyled(IOContext(io, :color => true), "string", color=:red)
julia> String(take!(io))
"\\e[31mstring\\e[39m"
julia> printstyled(io, "string", color=:red)
julia> String(take!(io))
"string"
```
```jldoctest
julia> print(IOContext(stdout, :compact => false), 1.12341234)
1.12341234
julia> print(IOContext(stdout, :compact => true), 1.12341234)
1.12341
```
```jldoctest
julia> function f(io::IO)
if get(io, :short, false)
print(io, "short")
else
print(io, "loooooong")
end
end
f (generic function with 1 method)
julia> f(stdout)
loooooong
julia> f(IOContext(stdout, :short => true))
short
```
"""
IOContext(io::IO, KV::Pair, KVs::Pair...) = IOContext(IOContext(io, KV), KVs...)
show(io::IO, ctx::IOContext) = (print(io, "IOContext("); show(io, ctx.io); print(io, ")"))
pipe_reader(io::IOContext) = io.io
pipe_writer(io::IOContext) = io.io
lock(io::IOContext) = lock(io.io)
unlock(io::IOContext) = unlock(io.io)
in(key_value::Pair, io::IOContext) = in(key_value, io.dict, ===)
in(key_value::Pair, io::IO) = false
haskey(io::IOContext, key) = haskey(io.dict, key)
haskey(io::IO, key) = false
getindex(io::IOContext, key) = getindex(io.dict, key)
getindex(io::IO, key) = throw(KeyError(key))
get(io::IOContext, key, default) = get(io.dict, key, default)
get(io::IO, key, default) = default
displaysize(io::IOContext) = haskey(io, :displaysize) ? io[:displaysize] : displaysize(io.io)
show_circular(io::IO, @nospecialize(x)) = false
function show_circular(io::IOContext, @nospecialize(x))
d = 1
for (k, v) in io.dict
if k === :SHOWN_SET
if v === x
print(io, "#= circular reference @-$d =#")
return true
end
d += 1
end
end
return false
end
"""
show(x)
Write an informative text representation of a value to the current output stream. New types
should overload `show(io::IO, x)` where the first argument is a stream. The representation used
by `show` generally includes Julia-specific formatting and type information.
[`repr`](@ref) returns the output of `show` as a string.
See also [`print`](@ref), which writes un-decorated representations.
# Examples
```jldoctest
julia> show("Hello World!")
"Hello World!"
julia> print("Hello World!")
Hello World!
```
"""
show(x) = show(stdout::IO, x)
show(io::IO, @nospecialize(x)) = show_default(io, x)
# avoid inferring show_default on the type of `x`
show_default(io::IO, @nospecialize(x)) = _show_default(io, inferencebarrier(x))
function _show_default(io::IO, @nospecialize(x))
t = typeof(x)
show(io, inferencebarrier(t))
print(io, '(')
nf = nfields(x)
nb = sizeof(x)
if nf != 0 || nb == 0
if !show_circular(io, x)
recur_io = IOContext(io, Pair{Symbol,Any}(:SHOWN_SET, x),
Pair{Symbol,Any}(:typeinfo, Any))
for i in 1:nf
f = fieldname(t, i)
if !isdefined(x, f)
print(io, undef_ref_str)
else
show(recur_io, getfield(x, i))
end
if i < nf
print(io, ", ")
end
end
end
else
print(io, "0x")
r = Ref(x)
GC.@preserve r begin
p = unsafe_convert(Ptr{Cvoid}, r)
for i in (nb - 1):-1:0
print(io, string(unsafe_load(convert(Ptr{UInt8}, p + i)), base = 16, pad = 2))
end
end
end
print(io,')')
end
# Check if a particular symbol is exported from a standard library module
function is_exported_from_stdlib(name::Symbol, mod::Module)
!isdefined(mod, name) && return false
orig = getfield(mod, name)
while !(mod === Base || mod === Core)
parent = parentmodule(mod)
if mod === Main || mod === parent || parent === Main
return false
end
mod = parent
end
return isexported(mod, name) && isdefined(mod, name) && !isdeprecated(mod, name) && getfield(mod, name) === orig
end
function show_function(io::IO, f::Function, compact::Bool)
ft = typeof(f)
mt = ft.name.mt
if mt === Symbol.name.mt
# uses shared method table
show_default(io, f)
elseif compact
print(io, mt.name)
elseif isdefined(mt, :module) && isdefined(mt.module, mt.name) &&
getfield(mt.module, mt.name) === f
if is_exported_from_stdlib(mt.name, mt.module) || mt.module === Main
print(io, mt.name)
else
print(io, mt.module, ".", mt.name)
end
else
show_default(io, f)
end
end
show(io::IO, f::Function) = show_function(io, f, get(io, :compact, false))
print(io::IO, f::Function) = show_function(io, f, true)
function show(io::IO, f::Core.IntrinsicFunction)
if !get(io, :compact, false)
print(io, "Core.Intrinsics.")
end
print(io, nameof(f))
end
print(io::IO, f::Core.IntrinsicFunction) = print(io, nameof(f))
show(io::IO, ::Core.TypeofBottom) = print(io, "Union{}")
show(io::IO, ::MIME"text/plain", ::Core.TypeofBottom) = print(io, "Union{}")
function print_without_params(@nospecialize(x))
if isa(x,UnionAll)
b = unwrap_unionall(x)
return isa(b,DataType) && b.name.wrapper === x
end
return false
end
has_typevar(@nospecialize(t), v::TypeVar) = ccall(:jl_has_typevar, Cint, (Any, Any), t, v)!=0
function io_has_tvar_name(io::IOContext, name::Symbol, @nospecialize(x))
for (key, val) in io.dict
if key === :unionall_env && val isa TypeVar && val.name === name && has_typevar(x, val)
return true
end
end
return false
end
io_has_tvar_name(io::IO, name::Symbol, @nospecialize(x)) = false
function show(io::IO, @nospecialize(x::Type))
if x isa DataType
show_datatype(io, x)
return
elseif x isa Union
print(io, "Union")
show_delim_array(io, uniontypes(x), '{', ',', '}', false)
return
end
x::UnionAll
if print_without_params(x)
return show(io, unwrap_unionall(x).name)
end
if x.var.name === :_ || io_has_tvar_name(io, x.var.name, x)
counter = 1
while true
newname = Symbol(x.var.name, counter)
if !io_has_tvar_name(io, newname, x)
newtv = TypeVar(newname, x.var.lb, x.var.ub)
x = UnionAll(newtv, x{newtv})
break
end
counter += 1
end
end
show(IOContext(io, :unionall_env => x.var), x.body)
print(io, " where ")
show(io, x.var)
end
# Check whether 'sym' (defined in module 'parent') is visible from module 'from'
# If an object with this name exists in 'from', we need to check that it's the same binding
# and that it's not deprecated.
function isvisible(sym::Symbol, parent::Module, from::Module)
owner = ccall(:jl_binding_owner, Any, (Any, Any), parent, sym)
from_owner = ccall(:jl_binding_owner, Any, (Any, Any), from, sym)
return owner !== nothing && from_owner === owner &&
!isdeprecated(parent, sym) &&
isdefined(from, sym) # if we're going to return true, force binding resolution
end
function show_type_name(io::IO, tn::Core.TypeName)
if tn === UnionAll.name
# by coincidence, `typeof(Type)` is a valid representation of the UnionAll type.
# intercept this case and print `UnionAll` instead.
return print(io, "UnionAll")
end
globname = isdefined(tn, :mt) ? tn.mt.name : nothing
globfunc = false
if globname !== nothing
globname_str = string(globname::Symbol)
if ('#' ∉ globname_str && '@' ∉ globname_str && isdefined(tn, :module) &&
isbindingresolved(tn.module, globname) && isdefined(tn.module, globname) &&
isconcretetype(tn.wrapper) && isa(getfield(tn.module, globname), tn.wrapper))
globfunc = true
end
end
sym = (globfunc ? globname : tn.name)::Symbol
globfunc && print(io, "typeof(")
quo = false
if !get(io, :compact, false)
# Print module prefix unless type is visible from module passed to
# IOContext If :module is not set, default to Main. nothing can be used
# to force printing prefix
from = get(io, :module, Main)
if isdefined(tn, :module) && (from === nothing || !isvisible(sym, tn.module, from))
show(io, tn.module)
print(io, ".")
if globfunc && !is_id_start_char(first(string(sym)))
print(io, ':')
if sym in quoted_syms
print(io, '(')
quo = true
end
end
end
end
show_sym(io, sym)
quo && print(io, ")")
globfunc && print(io, ")")
end
function show_datatype(io::IO, x::DataType)
istuple = x.name === Tuple.name
if (!isempty(x.parameters) || istuple) && x !== Tuple
n = length(x.parameters)::Int
# Print homogeneous tuples with more than 3 elements compactly as NTuple{N, T}
if istuple && n > 3 && all(i -> (x.parameters[1] === i), x.parameters)
print(io, "NTuple{", n, ',', x.parameters[1], "}")
else
show_type_name(io, x.name)
# Do not print the type parameters for the primary type if we are
# printing a method signature or type parameter.
# Always print the type parameter if we are printing the type directly
# since this information is still useful.
print(io, '{')
for (i, p) in enumerate(x.parameters)
show(io, p)
i < n && print(io, ',')
end
print(io, '}')
end
else
show_type_name(io, x.name)
end
end
function show_supertypes(io::IO, typ::DataType)
print(io, typ)
while typ != Any
typ = supertype(typ)
print(io, " <: ", typ)
end
end
show_supertypes(typ::DataType) = show_supertypes(stdout, typ)
"""
@show
Show an expression and result, returning the result. See also [`show`](@ref).
"""
macro show(exs...)
blk = Expr(:block)
for ex in exs
push!(blk.args, :(println($(sprint(show_unquoted,ex)*" = "),
repr(begin value=$(esc(ex)) end))))
end
isempty(exs) || push!(blk.args, :value)
return blk
end
function show(io::IO, tn::Core.TypeName)
show_type_name(io, tn)
end
show(io::IO, ::Nothing) = print(io, "nothing")
show(io::IO, b::Bool) = print(io, get(io, :typeinfo, Any) === Bool ? (b ? "1" : "0") : (b ? "true" : "false"))
show(io::IO, n::Signed) = (write(io, string(n)); nothing)
show(io::IO, n::Unsigned) = print(io, "0x", string(n, pad = sizeof(n)<<1, base = 16))
print(io::IO, n::Unsigned) = print(io, string(n))
show(io::IO, p::Ptr) = print(io, typeof(p), " @0x$(string(UInt(p), base = 16, pad = Sys.WORD_SIZE>>2))")
has_tight_type(p::Pair) =
typeof(p.first) == typeof(p).parameters[1] &&
typeof(p.second) == typeof(p).parameters[2]
isdelimited(io::IO, x) = true
isdelimited(io::IO, x::Function) = !isoperator(Symbol(x))
# !isdelimited means that the Pair is printed with "=>" (like in "1 => 2"),
# without its explicit type (like in "Pair{Integer,Integer}(1, 2)")
isdelimited(io::IO, p::Pair) = !(has_tight_type(p) || get(io, :typeinfo, Any) == typeof(p))
function gettypeinfos(io::IO, p::Pair)
typeinfo = get(io, :typeinfo, Any)
p isa typeinfo <: Pair ?
fieldtype(typeinfo, 1) => fieldtype(typeinfo, 2) :
Any => Any
end
function show(io::IO, p::Pair)
isdelimited(io, p) && return show_default(io, p)
typeinfos = gettypeinfos(io, p)
for i = (1, 2)
io_i = IOContext(io, :typeinfo => typeinfos[i])
isdelimited(io_i, p[i]) || print(io, "(")
show(io_i, p[i])
isdelimited(io_i, p[i]) || print(io, ")")
i == 1 && print(io, get(io, :compact, false) ? "=>" : " => ")
end
end
function show(io::IO, m::Module)
if is_root_module(m)
print(io, nameof(m))
else
print(io, join(fullname(m),"."))
end
end
function sourceinfo_slotnames(src::CodeInfo)
slotnames = src.slotnames
names = Dict{String,Int}()
printnames = Vector{String}(undef, length(slotnames))
for i in eachindex(slotnames)
name = string(slotnames[i])
idx = get!(names, name, i)
if idx != i || isempty(name)
printname = "$name@_$i"
idx > 0 && (printnames[idx] = "$name@_$idx")
names[name] = 0
else
printname = name
end
printnames[i] = printname
end
return printnames
end
function show(io::IO, l::Core.MethodInstance)
def = l.def
if isa(def, Method)
if isdefined(def, :generator) && l === def.generator
print(io, "MethodInstance generator for ")
show(io, def)
else
print(io, "MethodInstance for ")
show_tuple_as_call(io, def.name, l.specTypes)
end
else
print(io, "Toplevel MethodInstance thunk")
end
end
function show_delim_array(io::IO, itr::Union{AbstractArray,SimpleVector}, op, delim, cl,
delim_one, i1=first(LinearIndices(itr)), l=last(LinearIndices(itr)))
print(io, op)
if !show_circular(io, itr)
recur_io = IOContext(io, :SHOWN_SET => itr)
first = true
i = i1
if l >= i1
while true
if !isassigned(itr, i)
print(io, undef_ref_str)
else
x = itr[i]
show(recur_io, x)
end
i += 1
if i > l
delim_one && first && print(io, delim)
break
end
first = false
print(io, delim)
print(io, ' ')
end
end
end
print(io, cl)
end
function show_delim_array(io::IO, itr, op, delim, cl, delim_one, i1=1, n=typemax(Int))
print(io, op)
if !show_circular(io, itr)
recur_io = IOContext(io, :SHOWN_SET => itr)
y = iterate(itr)
first = true
i0 = i1-1
while i1 > 1 && y !== nothing
y = iterate(itr, y[2])
i1 -= 1
end
if y !== nothing
typeinfo = get(io, :typeinfo, Any)
while true
x = y[1]
y = iterate(itr, y[2])
show(IOContext(recur_io, :typeinfo => itr isa typeinfo <: Tuple ?
fieldtype(typeinfo, i1+i0) :
typeinfo),
x)
i1 += 1
if y === nothing || i1 > n
delim_one && first && print(io, delim)
break
end
first = false
print(io, delim)
print(io, ' ')
end
end
end
print(io, cl)
end
show(io::IO, t::Tuple) = show_delim_array(io, t, '(', ',', ')', true)
show(io::IO, v::SimpleVector) = show_delim_array(io, v, "svec(", ',', ')', false)
show(io::IO, s::Symbol) = show_unquoted_quote_expr(io, s, 0, 0, 0)
## Abstract Syntax Tree (AST) printing ##
# Summary:
# print(io, ex) defers to show_unquoted(io, ex)
# show(io, ex) defers to show_unquoted(io, QuoteNode(ex))
# show_unquoted(io, ex) does the heavy lifting
#
# AST printing should follow two rules:
# 1. Meta.parse(string(ex)) == ex
# 2. eval(Meta.parse(repr(ex))) == ex
#
# Rule 1 means that printing an expression should generate Julia code which
# could be reparsed to obtain the original expression. This code should be
# unambiguous and as readable as possible.
#
# Rule 2 means that showing an expression should generate a quoted version of
# print’s output. Parsing and then evaling this output should return the
# original expression.
#
# This is consistent with many other show methods, i.e.:
# show(Set([1,2,3])) # ==> "Set{Int64}([2,3,1])"
# eval(Meta.parse("Set{Int64}([2,3,1])”) # ==> An actual set
# While this isn’t true of ALL show methods, it is of all ASTs.
const ExprNode = Union{Expr, QuoteNode, Slot, LineNumberNode, SSAValue,
GotoNode, GlobalRef, PhiNode, PhiCNode, UpsilonNode,
Core.Compiler.GotoIfNot, Core.Compiler.ReturnNode}
# Operators have precedence levels from 1-N, and show_unquoted defaults to a
# precedence level of 0 (the fourth argument). The top-level print and show
# methods use a precedence of -1 to specially allow space-separated macro syntax.
# IOContext(io, :unquote_fallback => false) tells show_unquoted to treat any
# Expr whose head is :$ as if it is inside a quote, preventing fallback to the
# "unhandled" case: this is used by print/string to be lawful to Rule 1 above.
# On the countrary, show/repr have to follow Rule 2, requiring any Expr whose
# head is :$ and which is not inside a quote to fallback to the "unhandled" case:
# this is behavior is triggered by IOContext(io, :unquote_fallback => true)
print( io::IO, ex::ExprNode) = (show_unquoted(IOContext(io, :unquote_fallback => false), ex, 0, -1); nothing)
show( io::IO, ex::ExprNode) = show_unquoted_quote_expr(IOContext(io, :unquote_fallback => true), ex, 0, -1, 0)
show_unquoted(io::IO, ex) = show_unquoted(io, ex, 0, 0)
show_unquoted(io::IO, ex, indent::Int) = show_unquoted(io, ex, indent, 0)
show_unquoted(io::IO, ex, ::Int,::Int) = show(io, ex)
show_unquoted(io::IO, ex, indent::Int, prec::Int, ::Int) = show_unquoted(io, ex, indent, prec)
## AST printing constants ##
const indent_width = 4
const quoted_syms = Set{Symbol}([:(:),:(::),:(:=),:(=),:(==),:(===),:(=>)])
const uni_syms = Set{Symbol}([:(::), :(<:), :(>:)])
const uni_ops = Set{Symbol}([:(+), :(-), :(!), :(¬), :(~), :(<:), :(>:), :(√), :(∛), :(∜)])
const expr_infix_wide = Set{Symbol}([
:(=), :(+=), :(-=), :(*=), :(/=), :(\=), :(^=), :(&=), :(|=), :(÷=), :(%=), :(>>>=), :(>>=), :(<<=),
:(.=), :(.+=), :(.-=), :(.*=), :(./=), :(.\=), :(.^=), :(.&=), :(.|=), :(.÷=), :(.%=), :(.>>>=), :(.>>=), :(.<<=),
:(&&), :(||), :(<:), :($=), :(⊻=), :(>:)])
const expr_infix = Set{Symbol}([:(:), :(->), Symbol("::")])
const expr_infix_any = union(expr_infix, expr_infix_wide)
const expr_calls = Dict(:call => ('(',')'), :calldecl => ('(',')'),
:ref => ('[',']'), :curly => ('{','}'), :(.) => ('(',')'))
const expr_parens = Dict(:tuple=>('(',')'), :vcat=>('[',']'),
:hcat =>('[',']'), :row =>('[',']'), :vect=>('[',']'),
:braces=>('{','}'), :bracescat=>('{','}'))
## AST decoding helpers ##
is_id_start_char(c::AbstractChar) = ccall(:jl_id_start_char, Cint, (UInt32,), c) != 0
is_id_char(c::AbstractChar) = ccall(:jl_id_char, Cint, (UInt32,), c) != 0
function isidentifier(s::AbstractString)
isempty(s) && return false
(s == "true" || s == "false") && return false
c, rest = Iterators.peel(s)
is_id_start_char(c) || return false
return all(is_id_char, rest)
end
isidentifier(s::Symbol) = isidentifier(string(s))
"""
isoperator(s::Symbol)
Return `true` if the symbol can be used as an operator, `false` otherwise.
# Examples
```jldoctest
julia> Base.isoperator(:+), Base.isoperator(:f)
(true, false)
```
"""
isoperator(s::Union{Symbol,AbstractString}) = ccall(:jl_is_operator, Cint, (Cstring,), s) != 0
"""
isunaryoperator(s::Symbol)
Return `true` if the symbol can be used as a unary (prefix) operator, `false` otherwise.
# Examples
```jldoctest
julia> Base.isunaryoperator(:-), Base.isunaryoperator(:√), Base.isunaryoperator(:f)
(true, true, false)
```
"""
isunaryoperator(s::Symbol) = ccall(:jl_is_unary_operator, Cint, (Cstring,), s) != 0
is_unary_and_binary_operator(s::Symbol) = ccall(:jl_is_unary_and_binary_operator, Cint, (Cstring,), s) != 0
"""
isbinaryoperator(s::Symbol)
Return `true` if the symbol can be used as a binary (infix) operator, `false` otherwise.
# Examples
```jldoctest
julia> Base.isbinaryoperator(:-), Base.isbinaryoperator(:√), Base.isbinaryoperator(:f)
(true, false, false)
```
"""
isbinaryoperator(s::Symbol) = isoperator(s) && (!isunaryoperator(s) || is_unary_and_binary_operator(s))
"""
operator_precedence(s::Symbol)
Return an integer representing the precedence of operator `s`, relative to
other operators. Higher-numbered operators take precedence over lower-numbered
operators. Return `0` if `s` is not a valid operator.
# Examples
```jldoctest
julia> Base.operator_precedence(:+), Base.operator_precedence(:*), Base.operator_precedence(:.)
(11, 12, 17)
julia> Base.operator_precedence(:sin), Base.operator_precedence(:+=), Base.operator_precedence(:(=)) # (Note the necessary parens on `:(=)`)
(0, 1, 1)
```
"""
operator_precedence(s::Symbol) = Int(ccall(:jl_operator_precedence, Cint, (Cstring,), s))
operator_precedence(x::Any) = 0 # fallback for generic expression nodes
const prec_assignment = operator_precedence(:(=))
const prec_pair = operator_precedence(:(=>))
const prec_control_flow = operator_precedence(:(&&))
const prec_arrow = operator_precedence(:(-->))
const prec_comparison = operator_precedence(:(>))
const prec_power = operator_precedence(:(^))
const prec_decl = operator_precedence(:(::))
"""
operator_associativity(s::Symbol)
Return a symbol representing the associativity of operator `s`. Left- and right-associative
operators return `:left` and `:right`, respectively. Return `:none` if `s` is non-associative
or an invalid operator.
# Examples
```jldoctest
julia> Base.operator_associativity(:-), Base.operator_associativity(:+), Base.operator_associativity(:^)
(:left, :none, :right)
julia> Base.operator_associativity(:⊗), Base.operator_associativity(:sin), Base.operator_associativity(:→)
(:left, :none, :right)
```
"""
function operator_associativity(s::Symbol)
if operator_precedence(s) in (prec_arrow, prec_assignment, prec_control_flow, prec_pair, prec_power) ||
(isunaryoperator(s) && !is_unary_and_binary_operator(s)) || s === :<| || s === :||
return :right
elseif operator_precedence(s) in (0, prec_comparison) || s in (:+, :++, :*)
return :none
end
return :left
end
is_expr(@nospecialize(ex), head::Symbol) = isa(ex, Expr) && (ex.head === head)
is_expr(@nospecialize(ex), head::Symbol, n::Int) = is_expr(ex, head) && length(ex.args) == n
is_quoted(ex) = false
is_quoted(ex::QuoteNode) = true
is_quoted(ex::Expr) = is_expr(ex, :quote, 1) || is_expr(ex, :inert, 1)
unquoted(ex::QuoteNode) = ex.value
unquoted(ex::Expr) = ex.args[1]
## AST printing helpers ##
function printstyled end
function with_output_color end
const indent_width = 4
is_expected_union(u::Union) = u.a == Nothing || u.b == Nothing || u.a == Missing || u.b == Missing
emphasize(io, str::AbstractString, col = Base.error_color()) = get(io, :color, false) ?
printstyled(io, str; color=col, bold=true) :
print(io, uppercase(str))
show_linenumber(io::IO, line) = print(io, "#= line ", line, " =#")
show_linenumber(io::IO, line, file) = print(io, "#= ", file, ":", line, " =#")
show_linenumber(io::IO, line, file::Nothing) = show_linenumber(io, line)
# show a block, e g if/for/etc
function show_block(io::IO, head, args::Vector, body, indent::Int, quote_level::Int)
print(io, head)
if !isempty(args)
print(io, ' ')
if head === :elseif
show_list(io, args, " ", indent, 0, quote_level)
else
show_list(io, args, ", ", indent, 0, quote_level)
end
end
ind = head === :module || head === :baremodule ? indent : indent + indent_width
exs = (is_expr(body, :block) || is_expr(body, :quote)) ? body.args : Any[body]
for ex in exs
print(io, '\n', " "^ind)
show_unquoted(io, ex, ind, -1, quote_level)
end
print(io, '\n', " "^indent)
end
show_block(io::IO,head, block,i::Int, quote_level::Int) = show_block(io,head, [], block,i, quote_level)
function show_block(io::IO, head, arg, block, i::Int, quote_level::Int)
if is_expr(arg, :block) || is_expr(arg, :quote)
show_block(io, head, arg.args, block, i, quote_level)
else
show_block(io, head, Any[arg], block, i, quote_level)
end
end
# show an indented list
function show_list(io::IO, items, sep, indent::Int, prec::Int=0, quote_level::Int=0, enclose_operators::Bool=false,
kw::Bool=false)
n = length(items)
n == 0 && return
indent += indent_width
first = true
for item in items
!first && print(io, sep)
parens = !is_quoted(item) &&
(first && prec >= prec_power &&
((item isa Expr && item.head === :call && item.args[1] in uni_ops) ||
(item isa Real && item < 0))) ||
(enclose_operators && item isa Symbol && isoperator(item))
parens && print(io, '(')
if kw && is_expr(item, :kw, 2)
show_unquoted(io, Expr(:(=), item.args[1], item.args[2]), indent, parens ? 0 : prec, quote_level)
elseif kw && is_expr(item, :(=), 2)
show_unquoted_expr_fallback(io, item, indent, quote_level)
else
show_unquoted(io, item, indent, parens ? 0 : prec, quote_level)
end
parens && print(io, ')')
first = false
end
end
# show an indented list inside the parens (op, cl)
function show_enclosed_list(io::IO, op, items, sep, cl, indent, prec=0, quote_level=0, encl_ops=false, kw::Bool=false)
print(io, op)
show_list(io, items, sep, indent, prec, quote_level, encl_ops, kw)
print(io, cl)
end
# show a normal (non-operator) function call, e.g. f(x, y) or A[z]
# kw: `=` expressions are parsed with head `kw` in this context
function show_call(io::IO, head, func, func_args, indent, quote_level, kw::Bool)
op, cl = expr_calls[head]
if (isa(func, Symbol) && func !== :(:) && !(head === :. && isoperator(func))) ||
(isa(func, Expr) && (func.head === :. || func.head === :curly || func.head === :macroname)) ||
isa(func, GlobalRef)
show_unquoted(io, func, indent, 0, quote_level)
else
print(io, '(')
show_unquoted(io, func, indent, 0, quote_level)
print(io, ')')
end
if head === :(.)
print(io, '.')
end
if !isempty(func_args) && isa(func_args[1], Expr) && func_args[1].head === :parameters
print(io, op)
show_list(io, func_args[2:end], ", ", indent, 0, quote_level, false, kw)
print(io, "; ")
show_list(io, func_args[1].args, ", ", indent, 0, quote_level, false, kw)
print(io, cl)
else
show_enclosed_list(io, op, func_args, ", ", cl, indent, 0, quote_level, false, kw)
end
end
# Print `sym` as it would appear as an identifier name in code
# * Print valid identifiers & operators literally; also macros names if allow_macroname=true
# * Escape invalid identifiers with var"" syntax
function show_sym(io::IO, sym; allow_macroname=false)
if isidentifier(sym) || (isoperator(sym) && sym !== Symbol("'"))
print(io, sym)
elseif allow_macroname && (sym_str = string(sym); startswith(sym_str, '@'))
print(io, '@')
show_sym(io, sym_str[2:end])
else
print(io, "var", repr(string(sym)))
end
end
## AST printing ##
show_unquoted(io::IO, val::SSAValue, ::Int, ::Int) = print(io, "%", val.id)
show_unquoted(io::IO, sym::Symbol, ::Int, ::Int) = show_sym(io, sym, allow_macroname=false)
show_unquoted(io::IO, ex::LineNumberNode, ::Int, ::Int) = show_linenumber(io, ex.line, ex.file)
show_unquoted(io::IO, ex::GotoNode, ::Int, ::Int) = print(io, "goto %", ex.label)
show_unquoted(io::IO, ex::GlobalRef, ::Int, ::Int) = show_globalref(io, ex)
function show_globalref(io::IO, ex::GlobalRef; allow_macroname=false)
print(io, ex.mod)
print(io, '.')
quoted = !isidentifier(ex.name) && !startswith(string(ex.name), "@")
parens = quoted && (!isoperator(ex.name) || (ex.name in quoted_syms))
quoted && print(io, ':')
parens && print(io, '(')
show_sym(io, ex.name, allow_macroname=allow_macroname)
parens && print(io, ')')
nothing
end
function show_unquoted(io::IO, ex::Slot, ::Int, ::Int)
typ = isa(ex, TypedSlot) ? ex.typ : Any
slotid = ex.id
slotnames = get(io, :SOURCE_SLOTNAMES, false)
if (isa(slotnames, Vector{String}) &&
slotid <= length(slotnames::Vector{String}))
print(io, (slotnames::Vector{String})[slotid])
else
print(io, "_", slotid)
end
if typ !== Any && isa(ex, TypedSlot)
print(io, "::", typ)
end
end
function show_unquoted(io::IO, ex::QuoteNode, indent::Int, prec::Int)
if isa(ex.value, Symbol)
show_unquoted_quote_expr(io, ex.value, indent, prec, 0)
else
print(io, "\$(QuoteNode(")
# QuoteNode does not allows for interpolation, so if ex.value is an
# Expr it should be shown with quote_level equal to zero.
# Calling show(io, ex.value) like this implicitly enforce that.
show(io, ex.value)
print(io, "))")
end
end
function show_unquoted_quote_expr(io::IO, @nospecialize(value), indent::Int, prec::Int, quote_level::Int)
if isa(value, Symbol) && !(value in quoted_syms)
s = string(value)
if isidentifier(s) || (isoperator(value) && value !== Symbol("'"))
print(io, ":")
print(io, value)
else
print(io, "Symbol(", repr(s), ")")
end
else
if isa(value,Expr) && value.head === :block
show_block(IOContext(io, beginsym=>false), "quote", value, indent, quote_level)
print(io, "end")
else
print(io, ":(")
show_unquoted(io, value, indent+2, -1, quote_level) # +2 for `:(`
print(io, ")")
end
end
end
function show_generator(io, ex, indent, quote_level)
if ex.head === :flatten
fg = ex
ranges = Any[]
while isa(fg, Expr) && fg.head === :flatten
push!(ranges, fg.args[1].args[2:end])
fg = fg.args[1].args[1]
end
push!(ranges, fg.args[2:end])
show_unquoted(io, fg.args[1], indent, 0, quote_level)
for r in ranges
print(io, " for ")
show_list(io, r, ", ", indent, 0, quote_level)
end
else
show_unquoted(io, ex.args[1], indent, 0, quote_level)
print(io, " for ")
show_list(io, ex.args[2:end], ", ", indent, 0, quote_level)
end
end
function valid_import_path(@nospecialize ex)
return is_expr(ex, :(.)) && length((ex::Expr).args) > 0 && all(a->isa(a,Symbol), (ex::Expr).args)
end
function show_import_path(io::IO, ex, quote_level)
if !isa(ex, Expr)
show_unquoted(io, ex)
elseif ex.head === :(:)
show_import_path(io, ex.args[1], quote_level)
print(io, ": ")
for i = 2:length(ex.args)
if i > 2
print(io, ", ")
end
show_import_path(io, ex.args[i], quote_level)
end
elseif ex.head === :(.)
for i = 1:length(ex.args)
if i > 1 && ex.args[i-1] !== :(.)
print(io, '.')
end
show_sym(io, ex.args[i], allow_macroname=(i==length(ex.args)))
end
else
show_unquoted(io, ex, 0, 0, quote_level)
end
end
# Wrap symbols for macro names to allow them to be printed literally
function allow_macroname(ex)
if (ex isa Symbol && first(string(ex)) == '@') ||
ex isa GlobalRef ||
(is_expr(ex, :(.)) && length(ex.args) == 2 &&
(is_expr(ex.args[2], :quote) || ex.args[2] isa QuoteNode))
return Expr(:macroname, ex)
else
ex
end
end
function is_core_macro(arg, macro_name::AbstractString)
arg === GlobalRef(Core, Symbol(macro_name))
end
# symbol for IOContext flag signaling whether "begin" is treated
# as an ordinary symbol, which is true in indexing expressions.
const beginsym = gensym(:beginsym)
function show_unquoted_expr_fallback(io::IO, ex::Expr, indent::Int, quote_level::Int)
print(io, "\$(Expr(")
show(io, ex.head)
for arg in ex.args
print(io, ", ")
if isa(arg, Expr)
print(io, ":(")
show_unquoted(io, arg, indent, 0, quote_level+1)
print(io, ")")
else
show(io, arg)
end
end
print(io, "))")
end
# TODO: implement interpolated strings
function show_unquoted(io::IO, ex::Expr, indent::Int, prec::Int, quote_level::Int = 0)
head, args, nargs = ex.head, ex.args, length(ex.args)
unhandled = false
# dot (i.e. "x.y"), but not compact broadcast exps
if head === :(.) && (nargs != 2 || !is_expr(args[2], :tuple))
if nargs == 2 && is_quoted(args[2])
item = args[1]
# field
field = unquoted(args[2])
parens = !is_quoted(item) && !(item isa Symbol && isidentifier(item)) && !is_expr(item, :(.))
parens && print(io, '(')
show_unquoted(io, item, indent, 0, quote_level)
parens && print(io, ')')
# .
print(io, '.')
# item
parens = !(field isa Symbol) || (field in quoted_syms)
quoted = parens || isoperator(field)
quoted && print(io, ':')
parens && print(io, '(')
show_unquoted(io, field, indent, 0, quote_level)
parens && print(io, ')')
else
unhandled = true
end
# infix (i.e. "x <: y" or "x = y")
elseif (head in expr_infix_any && nargs==2)
func_prec = operator_precedence(head)
head_ = head in expr_infix_wide ? " $head " : head
if func_prec <= prec
show_enclosed_list(io, '(', args, head_, ')', indent, func_prec, quote_level, true)
else
show_list(io, args, head_, indent, func_prec, quote_level, true)
end
elseif head === :tuple
print(io, "(")
if nargs > 0 && is_expr(args[1], :parameters)
show_list(io, args[2:end], ", ", indent, 0, quote_level)
nargs == 2 && print(io, ',')
print(io, ";")
if !isempty(args[1].args)
print(io, " ")
end
show_list(io, args[1].args, ", ", indent, 0, quote_level, false, true)
else
show_list(io, args, ", ", indent, 0, quote_level)
nargs == 1 && print(io, ',')
end
print(io, ")")
# list-like forms, e.g. "[1, 2, 3]"
elseif haskey(expr_parens, head) || # :vcat etc.
head === :typed_vcat || head === :typed_hcat
# print the type and defer to the untyped case
if head === :typed_vcat || head === :typed_hcat
show_unquoted(io, args[1], indent, prec, quote_level)
if head === :typed_vcat
head = :vcat
else
head = :hcat
end
args = args[2:end]
nargs = nargs - 1
end
op, cl = expr_parens[head]
if head === :vcat || head === :bracescat
sep = "; "
elseif head === :hcat || head === :row
sep = " "
else
sep = ", "
end
head !== :row && print(io, op)
show_list(io, args, sep, indent, 0, quote_level)
if nargs == 1 && head === :vcat
print(io, ';')
end
head !== :row && print(io, cl)
# function call
elseif head === :call && nargs >= 1
func = args[1]
fname = isa(func, GlobalRef) ? func.name : func
func_prec = operator_precedence(fname)
if func_prec > 0 || fname in uni_ops
func = fname
end
func_args = args[2:end]
# :kw exprs are only parsed inside parenthesized calls
if any(a->is_expr(a, :kw), func_args) || (!isempty(func_args) && is_expr(func_args[1], :parameters))
show_call(io, head, func, func_args, indent, quote_level, true)
# scalar multiplication (i.e. "100x")
elseif (func === :* &&
length(func_args)==2 && isa(func_args[1], Real) && isa(func_args[2], Symbol))
if func_prec <= prec
show_enclosed_list(io, '(', func_args, "", ')', indent, func_prec, quote_level)
else
show_list(io, func_args, "", indent, func_prec, quote_level)
end
# unary operator (i.e. "!z")
elseif isa(func,Symbol) && func in uni_ops && length(func_args) == 1
show_unquoted(io, func, indent, 0, quote_level)
arg1 = func_args[1]
if isa(arg1, Expr) || (isa(arg1, Symbol) && isoperator(arg1))
show_enclosed_list(io, '(', func_args, ", ", ')', indent, func_prec)
else
show_unquoted(io, arg1, indent, func_prec, quote_level)
end
# binary operator (i.e. "x + y")
elseif func_prec > 0 # is a binary operator
na = length(func_args)
if (na == 2 || (na > 2 && func in (:+, :++, :*)) || (na == 3 && func === :(:))) &&
all(!isa(a, Expr) || a.head !== :... for a in func_args)
sep = func === :(:) ? "$func" : " $func "
if func_prec <= prec
show_enclosed_list(io, '(', func_args, sep, ')', indent, func_prec, quote_level, true)
else
show_list(io, func_args, sep, indent, func_prec, quote_level, true)
end
elseif na == 1
# 1-argument call to normally-binary operator
op, cl = expr_calls[head]
print(io, "(")
show_unquoted(io, func, indent, 0, quote_level)
print(io, ")")
show_enclosed_list(io, op, func_args, ", ", cl, indent, 0, quote_level)
else
show_call(io, head, func, func_args, indent, quote_level, true)
end
# normal function (i.e. "f(x,y)")
else
show_call(io, head, func, func_args, indent, quote_level, true)
end
# new expr
elseif head === :new || head === :splatnew
show_enclosed_list(io, "%$head(", args, ", ", ")", indent, 0, quote_level)
# other call-like expressions ("A[1,2]", "T{X,Y}", "f.(X,Y)")
elseif haskey(expr_calls, head) && nargs >= 1 # :ref/:curly/:calldecl/:(.)
funcargslike = head === :(.) ? args[2].args : args[2:end]
show_call(head == :ref ? IOContext(io, beginsym=>true) : io, head, args[1], funcargslike, indent, quote_level, head !== :curly)
# comprehensions
elseif head === :typed_comprehension && nargs == 2
show_unquoted(io, args[1], indent, 0, quote_level)
print(io, '[')
show_generator(io, args[2], indent, quote_level)
print(io, ']')
elseif head === :comprehension && nargs == 1
print(io, '[')
show_generator(io, args[1], indent, quote_level)
print(io, ']')
elseif (head === :generator && nargs >= 2) || (head === :flatten && nargs == 1)
print(io, '(')
show_generator(io, ex, indent, quote_level)
print(io, ')')
elseif head === :filter && nargs == 2
show_unquoted(io, args[2], indent, 0, quote_level)
print(io, " if ")
show_unquoted(io, args[1], indent, 0, quote_level)
# comparison (i.e. "x < y < z")
elseif head === :comparison && nargs >= 3 && (nargs&1==1)
comp_prec = minimum(operator_precedence, args[2:2:end])
if comp_prec <= prec
show_enclosed_list(io, '(', args, " ", ')', indent, comp_prec, quote_level)
else
show_list(io, args, " ", indent, comp_prec, quote_level)
end
# function calls need to transform the function from :call to :calldecl
# so that operators are printed correctly
elseif head === :function && nargs==2 && is_expr(args[1], :call)
show_block(IOContext(io, beginsym=>false), head, Expr(:calldecl, args[1].args...), args[2], indent, quote_level)
print(io, "end")
elseif (head === :function || head === :macro) && nargs == 1
print(io, head, ' ')
show_unquoted(IOContext(io, beginsym=>false), args[1])
print(io, " end")
elseif head === :do && nargs == 2
iob = IOContext(io, beginsym=>false)
show_unquoted(iob, args[1], indent, -1, quote_level)
print(io, " do ")
show_list(iob, args[2].args[1].args, ", ", 0, 0, quote_level)
for stmt in args[2].args[2].args
print(io, '\n', " "^(indent + indent_width))
show_unquoted(iob, stmt, indent + indent_width, -1, quote_level)
end
print(io, '\n', " "^indent)
print(io, "end")
# block with argument
elseif head in (:for,:while,:function,:macro,:if,:elseif,:let) && nargs==2
if is_expr(args[2], :block)
show_block(IOContext(io, beginsym=>false), head, args[1], args[2], indent, quote_level)
else
show_block(IOContext(io, beginsym=>false), head, args[1], Expr(:block, args[2]), indent, quote_level)
end
print(io, "end")
elseif (head === :if || head === :elseif) && nargs == 3
iob = IOContext(io, beginsym=>false)
show_block(iob, head, args[1], args[2], indent, quote_level)
if isa(args[3],Expr) && args[3].head === :elseif
show_unquoted(iob, args[3], indent, prec, quote_level)
else
show_block(iob, "else", args[3], indent, quote_level)
print(io, "end")
end
elseif head === :module && nargs==3 && isa(args[1],Bool)
show_block(IOContext(io, beginsym=>false), args[1] ? :module : :baremodule, args[2], args[3], indent, quote_level)
print(io, "end")
# type declaration
elseif head === :struct && nargs==3
show_block(IOContext(io, beginsym=>false), args[1] ? Symbol("mutable struct") : Symbol("struct"), args[2], args[3], indent, quote_level)
print(io, "end")
elseif head === :primitive && nargs == 2
print(io, "primitive type ")
show_list(io, args, ' ', indent, 0, quote_level)
print(io, " end")
elseif head === :abstract && nargs == 1
print(io, "abstract type ")
show_list(IOContext(io, beginsym=>false), args, ' ', indent, 0, quote_level)
print(io, " end")
# empty return (i.e. "function f() return end")
elseif head === :return && nargs == 1 && args[1] === nothing
print(io, head)
# type annotation (i.e. "::Int")
elseif head in uni_syms && nargs == 1
print(io, head)
show_unquoted(io, args[1], indent, 0, quote_level)
# var-arg declaration or expansion
# (i.e. "function f(L...) end" or "f(B...)")
elseif head === :(...) && nargs == 1
show_unquoted(io, args[1], indent, 0, quote_level)
print(io, "...")
elseif (nargs == 0 && head in (:break, :continue))
print(io, head)
elseif (nargs == 1 && head in (:return, :const)) ||
head in (:local, :global)
print(io, head, ' ')
show_list(io, args, ", ", indent, 0, quote_level)
elseif head === :export
print(io, head, ' ')
show_list(io, allow_macroname.(args), ", ", indent)
elseif head === :macrocall && nargs >= 2
# handle some special syntaxes
# `a b c`
if is_core_macro(args[1], "@cmd")
print(io, "`", args[3], "`")
# 11111111111111111111, 0xfffffffffffffffff, 1111...many digits...
elseif is_core_macro(args[1], "@int128_str") ||
is_core_macro(args[1], "@uint128_str") ||
is_core_macro(args[1], "@big_str")
print(io, args[3])
# x"y" and x"y"z
elseif isa(args[1], Symbol) && nargs >= 3 && isa(args[3], String) &&
startswith(string(args[1]::Symbol), "@") &&
endswith(string(args[1]::Symbol), "_str")
s = string(args[1]::Symbol)
print(io, s[2:prevind(s,end,4)], "\"")
escape_raw_string(io, args[3])
print(io, "\"")
if nargs == 4
print(io, args[4])
end
# general case
else
# first show the line number argument as a comment
if isa(args[2], LineNumberNode) || is_expr(args[2], :line)
print(io, args[2], ' ')
end
# Use the functional syntax unless specifically designated with
# prec=-1 and hide the line number argument from the argument list
mname = allow_macroname(args[1])
if prec >= 0
show_call(io, :call, mname, args[3:end], indent, quote_level, false)
else
show_args = Vector{Any}(undef, nargs - 1)
show_args[1] = mname
show_args[2:end] = args[3:end]
show_list(io, show_args, ' ', indent, 0, quote_level)
end
end
elseif head === :macroname && nargs == 1
arg1 = args[1]
if arg1 isa Symbol
show_sym(io, arg1, allow_macroname=true)
elseif arg1 isa GlobalRef
show_globalref(io, arg1, allow_macroname=true)
elseif is_expr(arg1, :(.)) && length(arg1.args) == 2
m = arg1.args[1]
if m isa Symbol || m isa GlobalRef || is_expr(m, :(.), 2)
show_unquoted(io, m)
else
print(io, "(")
show_unquoted(io, m)
print(io, ")")
end
print(io, '.')
if is_expr(arg1.args[2], :quote)
mname = arg1.args[2].args[1]
else
mname = arg1.args[2].value
end
if mname isa Symbol
show_sym(io, mname, allow_macroname=true)
else
show_unquoted(io, mname)
end
else
show_unquoted(io, arg1)
end
elseif head === :line && 1 <= nargs <= 2
show_linenumber(io, args...)
elseif head === :try && 3 <= nargs <= 4
iob = IOContext(io, beginsym=>false)
show_block(iob, "try", args[1], indent, quote_level)
if is_expr(args[3], :block)
show_block(iob, "catch", args[2] === false ? Any[] : args[2], args[3], indent, quote_level)
end
if nargs >= 4 && is_expr(args[4], :block)
show_block(iob, "finally", Any[], args[4], indent, quote_level)
end
print(io, "end")
elseif head === :block
# print as (...; ...; ...;) inside indexing expression
if get(io, beginsym, false)
print(io, '(')
ind = indent + indent_width
for i = 1:length(ex.args)
if i > 1
# if there was only a comment before the first semicolon, the expression would get parsed as a NamedTuple
if !(i == 2 && ex.args[1] isa LineNumberNode)
print(io, ';')
end
print(io, "\n", ' '^ind)
end
show_unquoted(io, ex.args[i], ind, -1, quote_level)
end
if length(ex.args) < 2
print(io, isempty(ex.args) ? ";;)" : ";)")
else
print(io, ')')
end
else
show_block(io, "begin", ex, indent, quote_level)
print(io, "end")
end
elseif head === :quote && nargs == 1 && isa(args[1], Symbol)
show_unquoted_quote_expr(IOContext(io, beginsym=>false), args[1]::Symbol, indent, 0, quote_level+1)
elseif head === :quote && nargs == 1 && is_expr(args[1], :block)
show_block(IOContext(io, beginsym=>false), "quote", Expr(:quote, args[1].args...), indent,
quote_level+1)
print(io, "end")
elseif head === :quote && nargs == 1
print(io, ":(")
show_unquoted(IOContext(io, beginsym=>false), args[1], indent+2, 0, quote_level+1)
print(io, ")")
elseif head === :quote
show_block(IOContext(io, beginsym=>false), "quote", ex, indent, quote_level+1)
print(io, "end")
elseif head === :gotoifnot && nargs == 2 && isa(args[2], Int)
print(io, "unless ")
show_unquoted(io, args[1], indent, 0, quote_level)
print(io, " goto %")
print(io, args[2]::Int)
elseif head === :string && nargs == 1 && isa(args[1], AbstractString)
show(io, args[1])
elseif head === :null
print(io, "nothing")
elseif head === :string
print(io, '"')
for x in args
if !isa(x,AbstractString)
print(io, "\$(")
if isa(x,Symbol) && !(x in quoted_syms)
show_sym(io, x)
else
show_unquoted(io, x, 0, 0, quote_level)
end
print(io, ")")
else
escape_string(io, x, "\"\$")
end
end
print(io, '"')
elseif (head === :& || head === :$) && nargs == 1
if head === :$
quote_level -= 1
end
if head === :$ && quote_level < 0 && get(io, :unquote_fallback, true)
unhandled = true
else
print(io, head)
a1 = args[1]
parens = (isa(a1,Expr) && !in(a1.head, (:tuple, :$, :vect, :braces))) ||
(isa(a1,Symbol) && isoperator(a1))
parens && print(io, "(")
show_unquoted(io, a1, 0, 0, quote_level)
parens && print(io, ")")
end
# transpose
elseif head === Symbol('\'') && nargs == 1
if isa(args[1], Symbol)
show_unquoted(io, args[1], 0, 0, quote_level)
else
print(io, "(")
show_unquoted(io, args[1], 0, 0, quote_level)
print(io, ")")
end
print(io, head)
# `where` syntax
elseif head === :where && nargs > 1
parens = 1 <= prec
parens && print(io, "(")
show_unquoted(io, args[1], indent, operator_precedence(:(::)), quote_level)
print(io, " where ")
if nargs == 2
show_unquoted(io, args[2], indent, 1, quote_level)
else
print(io, "{")
show_list(io, args[2:end], ", ", indent, 0, quote_level)
print(io, "}")
end
parens && print(io, ")")
elseif (head === :import || head === :using) &&
((nargs == 1 && (valid_import_path(args[1]) ||
(is_expr(args[1], :(:)) &&
length((args[1]::Expr).args) > 1 &&
all(valid_import_path, (args[1]::Expr).args)))) ||
all(valid_import_path, args))
print(io, head)
print(io, ' ')
first = true
for a in args
if !first
print(io, ", ")
end
first = false
show_import_path(io, a, quote_level)
end
elseif head === :meta && nargs >= 2 && args[1] === :push_loc
print(io, "# meta: location ", join(args[2:end], " "))
elseif head === :meta && nargs == 1 && args[1] === :pop_loc
print(io, "# meta: pop location")
elseif head === :meta && nargs == 2 && args[1] === :pop_loc
print(io, "# meta: pop locations ($(args[2]))")
# print anything else as "Expr(head, args...)"
else
unhandled = true
end
if unhandled
show_unquoted_expr_fallback(io, ex, indent, quote_level)
end
nothing
end
demangle_function_name(name::Symbol) = Symbol(demangle_function_name(string(name)))
function demangle_function_name(name::AbstractString)
demangle = split(name, '#')
# kw sorters and impl methods use the name scheme `f#...`
if length(demangle) >= 2 && demangle[1] != ""
return demangle[1]
end
return name
end
function show_tuple_as_call(io::IO, name::Symbol, sig::Type, demangle=false, kwargs=nothing)
# print a method signature tuple for a lambda definition
color = get(io, :color, false) && get(io, :backtrace, false) ? stackframe_function_color() : :nothing
if sig === Tuple
printstyled(io, demangle ? demangle_function_name(name) : name, "(...)", color=color)
return
end
tv = Any[]
env_io = io
while isa(sig, UnionAll)
push!(tv, sig.var)
env_io = IOContext(env_io, :unionall_env => sig.var)
sig = sig.body
end
sig = sig.parameters
with_output_color(color, env_io) do io
ft = sig[1]
uw = unwrap_unionall(ft)
if ft <: Function && isa(uw,DataType) && isempty(uw.parameters) &&
isdefined(uw.name.module, uw.name.mt.name) &&
ft == typeof(getfield(uw.name.module, uw.name.mt.name))
print(io, (demangle ? demangle_function_name : identity)(uw.name.mt.name))
elseif isa(ft, DataType) && ft.name === Type.body.name && !Core.Compiler.has_free_typevars(ft)
f = ft.parameters[1]
print(io, f)
else
print(io, "(::", ft, ")")
end
end
first = true
print_style = get(io, :color, false) && get(io, :backtrace, false) ? :bold : :nothing
printstyled(io, "(", color=print_style)
for i = 2:length(sig) # fixme (iter): `eachindex` with offset?
first || print(io, ", ")
first = false
print(env_io, "::", sig[i])
end
if kwargs !== nothing
print(io, "; ")
first = true
for (k, t) in kwargs
first || print(io, ", ")
first = false
print(io, k, "::")
show(io, t)
end
end
printstyled(io, ")", color=print_style)
show_method_params(io, tv)
nothing
end
resolvebinding(@nospecialize(ex)) = ex
resolvebinding(ex::QuoteNode) = ex.value
resolvebinding(ex::Symbol) = resolvebinding(GlobalRef(Main, ex))
function resolvebinding(ex::Expr)
if ex.head === :. && isa(ex.args[2], Symbol)
parent = resolvebinding(ex.args[1])
if isa(parent, Module)
return resolvebinding(GlobalRef(parent, ex.args[2]))
end
end
return nothing
end
function resolvebinding(ex::GlobalRef)
isdefined(ex.mod, ex.name) || return nothing
isconst(ex.mod, ex.name) || return nothing
m = getfield(ex.mod, ex.name)
isa(m, Module) || return nothing
return m
end
function ismodulecall(ex::Expr)
return ex.head === :call && (ex.args[1] === GlobalRef(Base,:getfield) ||
ex.args[1] === GlobalRef(Core,:getfield)) &&
isa(resolvebinding(ex.args[2]), Module)
end
function show(io::IO, tv::TypeVar)
# If we are in the `unionall_env`, the type-variable is bound
# and the type constraints are already printed.
# We don't need to print it again.
# Otherwise, the lower bound should be printed if it is not `Bottom`
# and the upper bound should be printed if it is not `Any`.
in_env = (:unionall_env => tv) in io
function show_bound(io::IO, @nospecialize(b))
parens = isa(b,UnionAll) && !print_without_params(b)
parens && print(io, "(")
show(io, b)
parens && print(io, ")")
end
lb, ub = tv.lb, tv.ub
if !in_env && lb !== Bottom
if ub === Any
show_unquoted(io, tv.name)
print(io, ">:")
show_bound(io, lb)
else
show_bound(io, lb)
print(io, "<:")
show_unquoted(io, tv.name)
end
else
show_unquoted(io, tv.name)
end
if !in_env && ub !== Any
print(io, "<:")
show_bound(io, ub)
end
nothing
end
module IRShow
const Compiler = Core.Compiler
using Core.IR
import ..Base
import .Compiler: IRCode, ReturnNode, GotoIfNot, CFG, scan_ssa_use!, Argument, isexpr, compute_basic_blocks, block_for_inst
Base.getindex(r::Compiler.StmtRange, ind::Integer) = Compiler.getindex(r, ind)
Base.size(r::Compiler.StmtRange) = Compiler.size(r)
Base.first(r::Compiler.StmtRange) = Compiler.first(r)
Base.last(r::Compiler.StmtRange) = Compiler.last(r)
include("compiler/ssair/show.jl")
const __debuginfo = Dict{Symbol, Any}(
# :full => src -> Base.IRShow.DILineInfoPrinter(src.linetable), # and add variable slot information
:source => src -> Base.IRShow.DILineInfoPrinter(src.linetable),
# :oneliner => src -> Base.IRShow.PartialLineInfoPrinter(src.linetable),
:none => src -> Base.IRShow.lineinfo_disabled,
)
const default_debuginfo = Ref{Symbol}(:none)
debuginfo(sym) = sym === :default ? default_debuginfo[] : sym
end
function show(io::IO, src::CodeInfo; debuginfo::Symbol=:source)
# Fix slot names and types in function body
print(io, "CodeInfo(")
lambda_io::IOContext = io
if src.slotnames !== nothing
lambda_io = IOContext(lambda_io, :SOURCE_SLOTNAMES => sourceinfo_slotnames(src))
end
@assert src.codelocs !== nothing
if isempty(src.linetable) || src.linetable[1] isa LineInfoNode
println(io)
# TODO: static parameter values?
# only accepts :source or :none, we can't have a fallback for default since
# that would break code_typed(, debuginfo=:source) iff IRShow.default_debuginfo[] = :none
IRShow.show_ir(lambda_io, src, IRShow.__debuginfo[debuginfo](src))
else
# this is a CodeInfo that has not been used as a method yet, so its locations are still LineNumberNodes
body = Expr(:block)
body.args = src.code
show(lambda_io, body)
end
print(io, ")")
end
function dump(io::IOContext, x::SimpleVector, n::Int, indent)
if isempty(x)
print(io, "empty SimpleVector")
return
end
print(io, "SimpleVector")
if n > 0
for i = 1:length(x)
println(io)
print(io, indent, " ", i, ": ")
if isassigned(x,i)
dump(io, x[i], n - 1, string(indent, " "))
else
print(io, undef_ref_str)
end
end
end
nothing
end
function dump(io::IOContext, @nospecialize(x), n::Int, indent)
if x === Union{}
show(io, x)
return
end
T = typeof(x)
if isa(x, Function)
print(io, x, " (function of type ", T, ")")
else
print(io, T)
end
nf = nfields(x)
if nf > 0
if n > 0 && !show_circular(io, x)
recur_io = IOContext(io, Pair{Symbol,Any}(:SHOWN_SET, x))
for field in 1:nf
println(io)
fname = string(fieldname(T, field))
print(io, indent, " ", fname, ": ")
if isdefined(x,field)
dump(recur_io, getfield(x, field), n - 1, string(indent, " "))
else
print(io, undef_ref_str)
end
end
end
elseif !isa(x, Function)
print(io, " ")
show(io, x)
end
nothing
end
dump(io::IOContext, x::Module, n::Int, indent) = print(io, "Module ", x)
dump(io::IOContext, x::String, n::Int, indent) = (print(io, "String "); show(io, x))
dump(io::IOContext, x::Symbol, n::Int, indent) = print(io, typeof(x), " ", x)
dump(io::IOContext, x::Union, n::Int, indent) = print(io, x)
dump(io::IOContext, x::Ptr, n::Int, indent) = print(io, x)
function dump_elts(io::IOContext, x::Array, n::Int, indent, i0, i1)
for i in i0:i1
print(io, indent, " ", i, ": ")
if !isassigned(x,i)
print(io, undef_ref_str)
else
dump(io, x[i], n - 1, string(indent, " "))
end
i < i1 && println(io)
end
end
function dump(io::IOContext, x::Array, n::Int, indent)
print(io, "Array{", eltype(x), "}(", size(x), ")")
if eltype(x) <: Number
print(io, " ")
show(io, x)
else
if n > 0 && !isempty(x) && !show_circular(io, x)
println(io)
recur_io = IOContext(io, :SHOWN_SET => x)
lx = length(x)
if get(io, :limit, false)
dump_elts(recur_io, x, n, indent, 1, (lx <= 10 ? lx : 5))
if lx > 10
println(io)
println(io, indent, " ...")
dump_elts(recur_io, x, n, indent, lx - 4, lx)
end
else
dump_elts(recur_io, x, n, indent, 1, lx)
end
end
end
nothing
end
# Types
function dump(io::IOContext, x::DataType, n::Int, indent)
print(io, x)
if x !== Any
print(io, " <: ", supertype(x))
end
if n > 0 && !(x <: Tuple) && !x.abstract
tvar_io::IOContext = io
for tparam in x.parameters
# approximately recapture the list of tvar parameterization
# that may be used by the internal fields
if isa(tparam, TypeVar)
tvar_io = IOContext(tvar_io, :unionall_env => tparam)
end
end
if x.name === NamedTuple_typename && !(x.parameters[1] isa Tuple)
# named tuple type with unknown field names
return
end
fields = fieldnames(x)
fieldtypes = datatype_fieldtypes(x)
for idx in 1:length(fields)
println(io)
print(io, indent, " ", fields[idx], "::")
print(tvar_io, fieldtypes[idx])
end
end
nothing
end
const DUMP_DEFAULT_MAXDEPTH = 8
function dump(io::IO, @nospecialize(x); maxdepth=DUMP_DEFAULT_MAXDEPTH)
dump(IOContext(io), x, maxdepth, "")
println(io)
end
"""
dump(x; maxdepth=$DUMP_DEFAULT_MAXDEPTH)
Show every part of the representation of a value.
The depth of the output is truncated at `maxdepth`.
# Examples
```jldoctest
julia> struct MyStruct
x
y
end
julia> x = MyStruct(1, (2,3));
julia> dump(x)
MyStruct
x: Int64 1
y: Tuple{Int64,Int64}
1: Int64 2
2: Int64 3
julia> dump(x; maxdepth = 1)
MyStruct
x: Int64 1
y: Tuple{Int64,Int64}
```
"""
function dump(arg; maxdepth=DUMP_DEFAULT_MAXDEPTH)
# this is typically used interactively, so default to being in Main
mod = get(stdout, :module, Main)
dump(IOContext(stdout::IO, :limit => true, :module => mod), arg; maxdepth=maxdepth)
end
"""
`alignment(X)` returns a tuple (left,right) showing how many characters are
needed on either side of an alignment feature such as a decimal point.
"""
alignment(io::IO, x::Any) = (0, length(sprint(show, x, context=io, sizehint=0)))
alignment(io::IO, x::Number) = (length(sprint(show, x, context=io, sizehint=0)), 0)
"`alignment(42)` yields (2,0)"
alignment(io::IO, x::Integer) = (length(sprint(show, x, context=io, sizehint=0)), 0)
"`alignment(4.23)` yields (1,3) for `4` and `.23`"
function alignment(io::IO, x::Real)
m = match(r"^(.*?)((?:[\.eEfF].*)?)$", sprint(show, x, context=io, sizehint=0))
m === nothing ? (length(sprint(show, x, context=io, sizehint=0)), 0) :
(length(m.captures[1]), length(m.captures[2]))
end
"`alignment(1 + 10im)` yields (3,5) for `1 +` and `_10im` (plus sign on left, space on right)"
function alignment(io::IO, x::Complex)
m = match(r"^(.*[^ef][\+\-])(.*)$", sprint(show, x, context=io, sizehint=0))
m === nothing ? (length(sprint(show, x, context=io, sizehint=0)), 0) :
(length(m.captures[1]), length(m.captures[2]))
end
function alignment(io::IO, x::Rational)
m = match(r"^(.*?/)(/.*)$", sprint(show, x, context=io, sizehint=0))
m === nothing ? (length(sprint(show, x, context=io, sizehint=0)), 0) :
(length(m.captures[1]), length(m.captures[2]))
end
function alignment(io::IO, x::Pair)
s = sprint(show, x, context=io, sizehint=0)
if !isdelimited(io, x) # i.e. use "=>" for display
ctx = IOContext(io, :typeinfo => gettypeinfos(io, x)[1])
left = length(sprint(show, x.first, context=ctx, sizehint=0))
left += 2 * !isdelimited(ctx, x.first) # for parens around p.first
left += !get(io, :compact, false) # spaces are added around "=>"
(left+1, length(s)-left-1) # +1 for the "=" part of "=>"
else
(0, length(s)) # as for x::Any
end
end
const undef_ref_str = "#undef"
"""
summary(io::IO, x)
str = summary(x)
Print to a stream `io`, or return a string `str`, giving a brief description of
a value. By default returns `string(typeof(x))`, e.g. [`Int64`](@ref).
For arrays, returns a string of size and type info,
e.g. `10-element Array{Int64,1}`.
# Examples
```jldoctest
julia> summary(1)
"Int64"
julia> summary(zeros(2))
"2-element Array{Float64,1}"
```
"""
summary(io::IO, x) = print(io, typeof(x))
function summary(x)
io = IOBuffer()
summary(io, x)
String(take!(io))
end
summary(io::IO, t::Tuple) = print(io, t)
## `summary` for AbstractArrays
# sizes such as 0-dimensional, 4-dimensional, 2x3
dims2string(d) = isempty(d) ? "0-dimensional" :
length(d) == 1 ? "$(d[1])-element" :
join(map(string,d), '×')
inds2string(inds) = join(map(_indsstring,inds), '×')
_indsstring(i) = string(i)
_indsstring(i::Union{IdentityUnitRange, Slice}) = string(i.indices)
# anything array-like gets summarized e.g. 10-element Array{Int64,1}
summary(io::IO, a::AbstractArray) = array_summary(io, a, axes(a))
function array_summary(io::IO, a, inds::Tuple{Vararg{OneTo}})
print(io, dims2string(length.(inds)), " ")
showarg(io, a, true)
end
function array_summary(io::IO, a, inds)
print(io, dims2string(length.(inds)), " ")
showarg(io, a, true)
print(io, " with indices ", inds2string(inds))
end
"""
showarg(io::IO, x, toplevel)
Show `x` as if it were an argument to a function. This function is
used by [`summary`](@ref) to display type information in terms of sequences of
function calls on objects. `toplevel` is `true` if this is
the direct call from `summary` and `false` for nested (recursive) calls.
The fallback definition is to print `x` as "::\\\$(typeof(x))",
representing argument `x` in terms of its type. (The double-colon is
omitted if `toplevel=true`.) However, you can
specialize this function for specific types to customize printing.
# Example
A SubArray created as `view(a, :, 3, 2:5)`, where `a` is a
3-dimensional Float64 array, has type
SubArray{Float64,2,Array{Float64,3},Tuple{Colon,Int64,UnitRange{Int64}},false}
The default `show` printing would display this full type.
However, the summary for SubArrays actually prints as
2×4 view(::Array{Float64,3}, :, 3, 2:5) with eltype Float64
because of a definition similar to
function Base.showarg(io::IO, v::SubArray, toplevel)
print(io, "view(")
showarg(io, parent(v), false)
print(io, ", ", join(v.indices, ", "))
print(io, ')')
toplevel && print(io, " with eltype ", eltype(v))
end
Note that we're calling `showarg` recursively for the parent array
type, indicating that any recursed calls are not at the top level.
Printing the parent as `::Array{Float64,3}` is the fallback (non-toplevel)
behavior, because no specialized method for `Array` has been defined.
"""
function showarg(io::IO, ::Type{T}, toplevel) where {T}
toplevel || print(io, "::")
print(io, "Type{", T, "}")
end
function showarg(io::IO, x, toplevel)
toplevel || print(io, "::")
print(io, typeof(x))
end
# This method resolves an ambiguity for packages that specialize on eltype
function showarg(io::IO, a::Array{Union{}}, toplevel)
toplevel || print(io, "::")
print(io, typeof(a))
end
# Container specializations
function showarg(io::IO, v::SubArray, toplevel)
print(io, "view(")
showarg(io, parent(v), false)
showindices(io, v.indices...)
print(io, ')')
toplevel && print(io, " with eltype ", eltype(v))
end
showindices(io, ::Union{Slice,IdentityUnitRange}, inds...) =
(print(io, ", :"); showindices(io, inds...))
showindices(io, ind1, inds...) =
(print(io, ", ", ind1); showindices(io, inds...))
showindices(io) = nothing
function showarg(io::IO, r::ReshapedArray, toplevel)
print(io, "reshape(")
showarg(io, parent(r), false)
print(io, ", ", join(r.dims, ", "))
print(io, ')')
toplevel && print(io, " with eltype ", eltype(r))
end
function showarg(io::IO, r::ReinterpretArray{T}, toplevel) where {T}
print(io, "reinterpret(", T, ", ")
showarg(io, parent(r), false)
print(io, ')')
end
# printing iterators from Base.Iterators
function show(io::IO, e::Iterators.Enumerate)
print(io, "enumerate(")
show(io, e.itr)
print(io, ')')
end
show(io::IO, z::Iterators.Zip) = show_delim_array(io, z.is, "zip(", ',', ')', false)
# pretty printing for Iterators.Pairs
function Base.showarg(io::IO, r::Iterators.Pairs{<:Integer, <:Any, <:Any, T}, toplevel) where T<:AbstractArray
print(io, "pairs(IndexLinear(), ::", T, ")")
end
function Base.showarg(io::IO, r::Iterators.Pairs{Symbol, <:Any, <:Any, T}, toplevel) where {T <: NamedTuple}
print(io, "pairs(::NamedTuple)")
end
function Base.showarg(io::IO, r::Iterators.Pairs{<:Any, <:Any, I, D}, toplevel) where {D, I}
print(io, "Iterators.Pairs(::", D, ", ::", I, ")")
end
# printing BitArrays
# (following functions not exported - mainly intended for debug)
function print_bit_chunk(io::IO, c::UInt64, l::Integer = 64)
for s = 0:l-1
d = (c >>> s) & 1
print(io, "01"[d + 1])
if (s + 1) & 7 == 0
print(io, " ")
end
end
end
print_bit_chunk(c::UInt64, l::Integer) = print_bit_chunk(stdout, c, l)
print_bit_chunk(c::UInt64) = print_bit_chunk(stdout, c)
function bitshow(io::IO, B::BitArray)
isempty(B) && return
Bc = B.chunks
for i = 1:length(Bc)-1
print_bit_chunk(io, Bc[i])
print(io, ": ")
end
l = _mod64(length(B)-1) + 1
print_bit_chunk(io, Bc[end], l)
end
bitshow(B::BitArray) = bitshow(stdout, B)
bitstring(B::BitArray) = sprint(bitshow, B)
