Revert "Deprecate DevNull, STDIN, STDOUT, and STDERR to lowercase (#2…

…5959)"

This reverts commit 446085a.
Lowercasing these identifiers conflicts with the statistical meaning of
`stderr`, i.e. the standard error. This is defined in StatsBase and
widely used.

DISTRIBUTING.md

@@ -375,7 +375,7 @@ for result in eachrow(results)
 end
 ```
 
-This will write color-coded lines to `stdout`.
+This will write color-coded lines to STDOUT.
 All lines in red must be investigated as they signify potential breakages caused by the
 backport version.
 Lines in yellow should be looked into since it means a package ran on one version but

NEWS.md

@@ -1116,9 +1116,6 @@ Deprecated or removed
   * The fallback method `^(x, p::Integer)` is deprecated. If your type relied on this definition,
     add a method such as `^(x::MyType, p::Integer) = Base.power_by_squaring(x, p)` ([#23332]).
 
-  * `DevNull`, `STDIN`, `STDOUT`, and `STDERR` have been renamed to `devnull`, `stdin`, `stdout`,
-    and `stderr`, respectively ([#25786]).
-
   * `wait` and `fetch` on `Task` now resemble the interface of `Future`.
 
   * `showcompact(io, x...)` has been deprecated in favor of
@@ -1128,6 +1125,8 @@ Deprecated or removed
   * `isupper`, `islower`, `ucfirst` and `lcfirst` have been deprecated in favor of `isuppercase`,
     `islowercase`, `uppercasefirst` and `lowercasefirst`, respectively ([#26442]).
 
+  * `wait` and `fetch` on `Task` now resemble the interface of `Future`
+
 Command-line option changes
 ---------------------------
 
@@ -1436,4 +1435,4 @@ Command-line option changes
 [#26286]: https://github.com/JuliaLang/julia/issues/26286
 [#26436]: https://github.com/JuliaLang/julia/issues/26436
 [#26442]: https://github.com/JuliaLang/julia/issues/26442
-[#26600]: https://github.com/JuliaLang/julia/issues/26600
+[#26600]: https://github.com/JuliaLang/julia/issues/26600

base/boot.jl

@@ -443,8 +443,8 @@ atdoc!(λ) = global atdoc = λ
 abstract type IO end
 struct CoreSTDOUT <: IO end
 struct CoreSTDERR <: IO end
-const stdout = CoreSTDOUT()
-const stderr = CoreSTDERR()
+const STDOUT = CoreSTDOUT()
+const STDERR = CoreSTDERR()
 io_pointer(::CoreSTDOUT) = Intrinsics.pointerref(Intrinsics.cglobal(:jl_uv_stdout, Ptr{Cvoid}), 1, 1)
 io_pointer(::CoreSTDERR) = Intrinsics.pointerref(Intrinsics.cglobal(:jl_uv_stderr, Ptr{Cvoid}), 1, 1)
 
@@ -468,9 +468,9 @@ print(io::IO, @nospecialize(x), @nospecialize a...) = (print(io, x); print(io, a
 println(io::IO) = (write(io, 0x0a); nothing) # 0x0a = '\n'
 println(io::IO, @nospecialize x...) = (print(io, x...); println(io))
 
-show(@nospecialize a) = show(stdout, a)
-print(@nospecialize a...) = print(stdout, a...)
-println(@nospecialize a...) = println(stdout, a...)
+show(@nospecialize a) = show(STDOUT, a)
+print(@nospecialize a...) = print(STDOUT, a...)
+println(@nospecialize a...) = println(STDOUT, a...)
 
 struct GeneratedFunctionStub
     gen

base/client.jl

@@ -165,7 +165,7 @@ function display_error(io::IO, er, bt)
     showerror(IOContext(io, :limit => true), er, bt)
     println(io)
 end
-display_error(er, bt) = display_error(stderr, er, bt)
+display_error(er, bt) = display_error(STDERR, er, bt)
 display_error(er) = display_error(er, [])
 
 function eval_user_input(@nospecialize(ast), show_value::Bool)
@@ -189,7 +189,7 @@ function eval_user_input(@nospecialize(ast), show_value::Bool)
                     try
                         invokelatest(display, value)
                     catch err
-                        println(stderr, "Evaluation succeeded, but an error occurred while showing value of type ", typeof(value), ":")
+                        println(STDERR, "Evaluation succeeded, but an error occurred while showing value of type ", typeof(value), ":")
                         rethrow(err)
                     end
                     println()
@@ -198,17 +198,17 @@ function eval_user_input(@nospecialize(ast), show_value::Bool)
             break
         catch err
             if errcount > 0
-                println(stderr, "SYSTEM: show(lasterr) caused an error")
+                println(STDERR, "SYSTEM: show(lasterr) caused an error")
             end
             errcount, lasterr = errcount+1, err
             if errcount > 2
-                println(stderr, "WARNING: it is likely that something important is broken, and Julia will not be able to continue normally")
+                println(STDERR, "WARNING: it is likely that something important is broken, and Julia will not be able to continue normally")
                 break
             end
             bt = catch_backtrace()
         end
     end
-    isa(stdin, TTY) && println()
+    isa(STDIN, TTY) && println()
     nothing
 end
 
@@ -328,7 +328,7 @@ function exec_options(opts)
     end
     repl |= is_interactive
     if repl
-        interactiveinput = isa(stdin, TTY)
+        interactiveinput = isa(STDIN, TTY)
         if interactiveinput
             global is_interactive = true
             banner = (opts.banner != 0) # --banner!=no
@@ -369,8 +369,8 @@ function __atreplinit(repl)
         try
             f(repl)
         catch err
-            showerror(stderr, err)
-            println(stderr)
+            showerror(STDERR, err)
+            println(STDERR)
         end
     end
 end
@@ -397,7 +397,7 @@ function run_main_repl(interactive::Bool, quiet::Bool, banner::Bool, history_fil
     if interactive && isassigned(REPL_MODULE_REF)
         invokelatest(REPL_MODULE_REF[]) do REPL
             term_env = get(ENV, "TERM", @static Sys.iswindows() ? "" : "dumb")
-            term = REPL.Terminals.TTYTerminal(term_env, stdin, stdout, stderr)
+            term = REPL.Terminals.TTYTerminal(term_env, STDIN, STDOUT, STDERR)
             color_set || (global have_color = REPL.Terminals.hascolor(term))
             banner && REPL.banner(term, term)
             if term.term_type == "dumb"
@@ -419,7 +419,7 @@ function run_main_repl(interactive::Bool, quiet::Bool, banner::Bool, history_fil
             @warn "REPL provider not available: using basic fallback"
         end
         banner && Base.banner()
-        let input = stdin
+        let input = STDIN
             if isa(input, File) || isa(input, IOStream)
                 # for files, we can slurp in the whole thing at once
                 ex = parse_input_line(read(input, String))
@@ -437,7 +437,7 @@ function run_main_repl(interactive::Bool, quiet::Bool, banner::Bool, history_fil
                 while isopen(input) || !eof(input)
                     if interactive
                         print("julia> ")
-                        flush(stdout)
+                        flush(STDOUT)
                     end
                     eval_user_input(parse_input_line(input), true)
                 end

base/clipboard.jl

@@ -4,7 +4,7 @@
 
 if Sys.isapple()
     function clipboard(x)
-        open(pipeline(`pbcopy`, stderr=stderr), "w") do io
+        open(pipeline(`pbcopy`, stderr=STDERR), "w") do io
             print(io, x)
         end
     end
@@ -28,7 +28,7 @@ elseif Sys.islinux() || Sys.KERNEL === :FreeBSD
         global _clipboardcmd
         _clipboardcmd !== nothing && return _clipboardcmd
         for cmd in (:xclip, :xsel)
-            success(pipeline(`which $cmd`, devnull)) && return _clipboardcmd = cmd
+            success(pipeline(`which $cmd`, DevNull)) && return _clipboardcmd = cmd
         end
         pkgs = @static if Sys.islinux()
             "xsel or xclip"
@@ -43,7 +43,7 @@ elseif Sys.islinux() || Sys.KERNEL === :FreeBSD
         if cmd === nothing
             error("unexpected clipboard command: $c")
         end
-        open(pipeline(cmd, stderr=stderr), "w") do io
+        open(pipeline(cmd, stderr=STDERR), "w") do io
             print(io, x)
         end
     end
@@ -53,7 +53,7 @@ elseif Sys.islinux() || Sys.KERNEL === :FreeBSD
         if cmd === nothing
             error("unexpected clipboard command: $c")
         end
-        read(pipeline(cmd, stderr=stderr), String)
+        read(pipeline(cmd, stderr=STDERR), String)
     end
 
 elseif Sys.iswindows()

base/compiler/bootstrap.jl

@@ -15,7 +15,7 @@ let fs = Any[typeinf_ext, typeinf, typeinf_edge, pure_eval_call, optimize, run_p
             x = T_IFUNC[i]
             push!(fs, x[3])
         else
-            println(stderr, "WARNING: tfunc missing for ", reinterpret(IntrinsicFunction, Int32(i)))
+            println(STDERR, "WARNING: tfunc missing for ", reinterpret(IntrinsicFunction, Int32(i)))
         end
     end
     for f in fs

base/compiler/compiler.jl

@@ -4,7 +4,7 @@ getfield(getfield(Main, :Core), :eval)(getfield(Main, :Core), :(baremodule Compi
 
 using Core.Intrinsics, Core.IR
 
-import Core: print, println, show, write, unsafe_write, stdout, stderr,
+import Core: print, println, show, write, unsafe_write, STDOUT, STDERR,
              _apply, svec, apply_type, Builtin, IntrinsicFunction, MethodInstance
 
 const getproperty = getfield

base/compiler/optimize.jl

@@ -3827,7 +3827,7 @@ macro check_ast(ctx, ex)
             println("Code:")
             println(ctx.sv.src)
             println("Value Info Map:")
-            show_info(stdout, ctx.infomap, ctx)
+            show_info(STDOUT, ctx.infomap, ctx)
             ccall(:abort, Union{}, ())
         end
     end

base/compiler/validation.jl

@@ -61,10 +61,10 @@ function validate_code_in_debug_mode(linfo::MethodInstance, src::CodeInfo, kind:
         if !isempty(errors)
             for e in errors
                 if linfo.def isa Method
-                    println(stderr, "WARNING: Encountered invalid ", kind, " code for method ",
+                    println(STDERR, "WARNING: Encountered invalid ", kind, " code for method ",
                             linfo.def, ": ", e)
                 else
-                    println(stderr, "WARNING: Encountered invalid ", kind, " code for top level expression in ",
+                    println(STDERR, "WARNING: Encountered invalid ", kind, " code for top level expression in ",
                             linfo.def, ": ", e)
                 end
             end

base/coreio.jl

@@ -1,11 +1,11 @@
 # This file is a part of Julia. License is MIT: https://julialang.org/license
 
-print(xs...)   = print(stdout::IO, xs...)
-println(xs...) = println(stdout::IO, xs...)
+print(xs...)   = print(STDOUT::IO, xs...)
+println(xs...) = println(STDOUT::IO, xs...)
 println(io::IO) = print(io, '\n')
 
 struct DevNullStream <: IO end
-const devnull = DevNullStream()
+const DevNull = DevNullStream()
 isreadable(::DevNullStream) = false
 iswritable(::DevNullStream) = true
 isopen(::DevNullStream) = true
@@ -26,6 +26,6 @@ let CoreIO = Union{Core.CoreSTDOUT, Core.CoreSTDERR}
     unsafe_write(io::CoreIO, x::Ptr{UInt8}, nb::UInt) = Core.unsafe_write(io, x, nb)
 end
 
-stdin = devnull
-stdout = Core.stdout
-stderr = Core.stderr
+STDIN = DevNull
+STDOUT = Core.STDOUT
+STDERR = Core.STDERR

base/deprecated.jl

@@ -127,7 +127,7 @@ macro deprecate_binding(old, new, export_old=true, dep_message=:nothing, constan
     return Expr(:toplevel,
          export_old ? Expr(:export, esc(old)) : nothing,
          Expr(:const, Expr(:(=), esc(Symbol(string("_dep_message_",old))), esc(dep_message))),
-         constant ? Expr(:const, Expr(:(=), esc(old), esc(new))) : Expr(:(=), esc(old), esc(new)),
+         Expr(:const, Expr(:(=), esc(old), esc(new))),
          Expr(:call, :deprecate, __module__, Expr(:quote, old)))
 end
 
@@ -966,14 +966,14 @@ function info(io::IO, msg...; prefix="INFO: ")
     print(io, String(take!(buf)))
     return
 end
-info(msg...; prefix="INFO: ") = info(stderr, msg..., prefix=prefix)
+info(msg...; prefix="INFO: ") = info(STDERR, msg..., prefix=prefix)
 
 # print a warning only once
 
 const have_warned = Set()
 
 warn_once(io::IO, msg...) = warn(io, msg..., once=true)
-warn_once(msg...) = warn(stderr, msg..., once=true)
+warn_once(msg...) = warn(STDERR, msg..., once=true)
 
 """
     warn([io, ] msg..., [prefix="WARNING: ", once=false, key=nothing, bt=nothing, filename=nothing, lineno::Int=0])
@@ -1023,19 +1023,19 @@ julia> warn("Beep Beep")
 WARNING: Beep Beep
 ```
 """
-warn(msg...; kw...) = warn(stderr, msg...; kw...)
+warn(msg...; kw...) = warn(STDERR, msg...; kw...)
 
 warn(io::IO, err::Exception; prefix="ERROR: ", kw...) =
     warn(io, sprint(showerror, err), prefix=prefix; kw...)
 
 warn(err::Exception; prefix="ERROR: ", kw...) =
-    warn(stderr, err, prefix=prefix; kw...)
+    warn(STDERR, err, prefix=prefix; kw...)
 
 info(io::IO, err::Exception; prefix="ERROR: ", kw...) =
     info(io, sprint(showerror, err), prefix=prefix; kw...)
 
 info(err::Exception; prefix="ERROR: ", kw...) =
-    info(stderr, err, prefix=prefix; kw...)
+    info(STDERR, err, prefix=prefix; kw...)
 
 # issue #25082
 @deprecate_binding Void Nothing
@@ -1487,13 +1487,6 @@ function (r::Regex)(s)
     occursin(r, s)
 end
 
-# Issue #25786
-@deprecate_binding DevNull devnull
-# TODO: When these are removed, also remove the uppercase variants in libuv.jl and stream.jl
-@deprecate_binding STDIN stdin true nothing false
-@deprecate_binding STDOUT stdout true nothing false
-@deprecate_binding STDERR stderr true nothing false
-
 # PR 25062
 @deprecate(link_pipe(pipe; julia_only_read = true, julia_only_write = true),
            link_pipe!(pipe, reader_supports_async = julia_only_read, writer_supports_async = julia_only_write),
@@ -1553,7 +1546,7 @@ end
 @deprecate Crand Libc.rand false
 @deprecate Csrand Libc.srand false
 
-@deprecate showcompact(x) show(IOContext(stdout, :compact => true), x)
+@deprecate showcompact(x) show(IOContext(STDOUT, :compact => true), x)
 @deprecate showcompact(io, x) show(IOContext(io, :compact => true), x)
 @deprecate sprint(::typeof(showcompact), args...) sprint(show, args...; context=:compact => true)
 

base/docs/basedocs.jl

@@ -789,16 +789,16 @@ A variable referring to the last computed value, automatically set at the intera
 kw"ans"
 
 """
-    devnull
+    DevNull
 
 Used in a stream redirect to discard all data written to it. Essentially equivalent to
 /dev/null on Unix or NUL on Windows. Usage:
 
 ```julia
-run(pipeline(`cat test.txt`, devnull))
+run(pipeline(`cat test.txt`, DevNull))
 ```
 """
-devnull
+DevNull
 
 # doc strings for code in boot.jl and built-ins
 

base/download.jl

@@ -19,7 +19,7 @@ else
         global downloadcmd
         if downloadcmd === nothing
             for checkcmd in (:curl, :wget, :fetch)
-                if success(pipeline(`which $checkcmd`, devnull))
+                if success(pipeline(`which $checkcmd`, DevNull))
                     downloadcmd = checkcmd
                     break
                 end

base/errorshow.jl

@@ -290,7 +290,7 @@ function showerror_ambiguous(io::IO, meth, f, args)
 end
 
 #Show an error by directly calling jl_printf.
-#Useful in Base submodule __init__ functions where stderr isn't defined yet.
+#Useful in Base submodule __init__ functions where STDERR isn't defined yet.
 function showerror_nostdio(err, msg::AbstractString)
     stderr_stream = ccall(:jl_stderr_stream, Ptr{Cvoid}, ())
     ccall(:jl_printf, Cint, (Ptr{Cvoid},Cstring), stderr_stream, msg)

base/exports.jl

@@ -40,6 +40,7 @@ export
     DenseMatrix,
     DenseVecOrMat,
     DenseVector,
+    DevNull,
     Dict,
     Dims,
     Enum,
@@ -134,11 +135,10 @@ export
     ENV,
     LOAD_PATH,
     PROGRAM_FILE,
-    stderr,
-    stdin,
-    stdout,
+    STDERR,
+    STDIN,
+    STDOUT,
     VERSION,
-    devnull,
 
 # Mathematical constants
     Inf,

base/initdefs.jl

@@ -140,8 +140,8 @@ function _atexit()
         try
             f()
         catch err
-            show(stderr, err)
-            println(stderr)
+            show(STDERR, err)
+            println(STDERR)
         end
     end
 end