deprecate whos to varinfo returning a markdown table. fixes #12131.

NEWS.md

@@ -404,6 +404,9 @@ Deprecated or removed
   * Using Bool values directly as indices is now deprecated and will be an error in the future. Convert
     them to `Int` before indexing if you intend to access index `1` for `true` and `0` for `false`.
 
+  * `whos` has been renamed `varinfo`, and now returns a markdown table instead of printing
+    output ([#12131]).
+
   * `writecsv(io, a; opts...)` has been deprecated in favor of
     `writedlm(io, a, ','; opts...)` ([#23529]).
 

base/deprecated.jl

@@ -1927,6 +1927,14 @@ end
     nothing
 end
 
+@deprecate whos(io::IO, m::Module, pat::Regex) show(io, varinfo(m, pat))
+@deprecate whos(io::IO, m::Module)             show(io, varinfo(m))
+@deprecate whos(io::IO)                        show(io, varinfo())
+@deprecate whos(m::Module, pat::Regex)         varinfo(m, pat)
+@deprecate whos(m::Module)                     varinfo(m)
+@deprecate whos(pat::Regex)                    varinfo(pat)
+@deprecate whos()                              varinfo()
+
 # indexing with A[true] will throw an argument error in the future
 function to_index(i::Bool)
     depwarn("indexing with Bool values is deprecated. Convert the index to an integer first with `Int(i)`.", (:getindex, :setindex!, :view))

base/exports.jl

@@ -953,9 +953,9 @@ export
     module_name,
     module_parent,
     names,
+    varinfo,
     versioninfo,
     which,
-    whos,
     workspace,
     @isdefined,
 

base/interactiveutil.jl

@@ -731,54 +731,24 @@ end
 
 
 """
-    whos(io::IO=STDOUT, m::Module=Main, pattern::Regex=r"")
+    varinfo(m::Module=Main, pattern::Regex=r"")
 
-Print information about exported global variables in a module, optionally restricted to those matching `pattern`.
+Return a markdown table giving information about exported global variables in a module, optionally restricted
+to those matching `pattern`.
 
 The memory consumption estimate is an approximate lower bound on the size of the internal structure of the object.
 """
-function whos(io::IO=STDOUT, m::Module=Main, pattern::Regex=r"")
-    maxline = displaysize(io)[2]
-    line = zeros(UInt8, maxline)
-    head = PipeBuffer(maxline + 1)
-    for v in sort!(names(m))
-        s = string(v)
-        if isdefined(m, v) && ismatch(pattern, s)
-            value = getfield(m, v)
-            @printf head "%30s " s
-            try
-                if value ∈ (Base, Main, Core)
-                    print(head, "              ")
-                else
-                    bytes = summarysize(value)
-                    if bytes < 10_000
-                        @printf(head, "%6d bytes  ", bytes)
-                    else
-                        @printf(head, "%6d KB     ", bytes ÷ (1024))
-                    end
-                end
-                print(head, summary(value))
-            catch e
-                print(head, "#=ERROR: unable to show value=#")
-            end
-            newline = search(head, UInt8('\n')) - 1
-            if newline < 0
-                newline = nb_available(head)
-            end
-            if newline > maxline
-                newline = maxline - 1 # make space for ...
-            end
-            line = resize!(line, newline)
-            line = read!(head, line)
+function varinfo(m::Module=Main, pattern::Regex=r"")
+    rows =
+        Any[ let value = getfield(m, v)
+                 Any[string(v),
+                     (value ∈ (Base, Main, Core) ? "" : format_bytes(summarysize(value))),
+                     summary(value)]
+             end
+             for v in sort!(names(m)) if isdefined(m, v) && ismatch(pattern, string(v)) ]
 
-            write(io, line)
-            if nb_available(head) > 0 # more to read? replace with ...
-                print(io, '\u2026') # hdots
-            end
-            println(io)
-            seekend(head) # skip the rest of the text
-        end
-    end
+    unshift!(rows, Any["name", "size", "summary"])
+
+    return Markdown.MD(Any[Markdown.Table(rows, Symbol[:l, :r, :l])])
 end
-whos(m::Module, pat::Regex=r"") = whos(STDOUT, m, pat)
-whos(pat::Regex) = whos(STDOUT, Main, pat)
+varinfo(pat::Regex) = varinfo(Main, pat)

base/util.jl

@@ -96,21 +96,25 @@ function padded_nonzero_print(value,str)
     end
 end
 
+function format_bytes(bytes)
+    bytes, mb = prettyprint_getunits(bytes, length(_mem_units), Int64(1024))
+    if mb == 1
+        @sprintf("%d %s%s", bytes, _mem_units[mb], bytes==1 ? "" : "s")
+    else
+        @sprintf("%.3f %s", bytes, _mem_units[mb])
+    end
+end
+
 function time_print(elapsedtime, bytes, gctime, allocs)
     @printf("%10.6f seconds", elapsedtime/1e9)
     if bytes != 0 || allocs != 0
-        bytes, mb = prettyprint_getunits(bytes, length(_mem_units), Int64(1024))
         allocs, ma = prettyprint_getunits(allocs, length(_cnt_units), Int64(1000))
         if ma == 1
             @printf(" (%d%s allocation%s: ", allocs, _cnt_units[ma], allocs==1 ? "" : "s")
         else
             @printf(" (%.2f%s allocations: ", allocs, _cnt_units[ma])
         end
-        if mb == 1
-            @printf("%d %s%s", bytes, _mem_units[mb], bytes==1 ? "" : "s")
-        else
-            @printf("%.3f %s", bytes, _mem_units[mb])
-        end
+        print(format_bytes(bytes))
         if gctime > 0
             @printf(", %.2f%% gc time", 100*gctime/elapsedtime)
         end

doc/src/manual/faq.md

@@ -567,11 +567,12 @@ julia> remotecall_fetch(()->gvar_self, 2)
 "Node1"
 
 julia> remotecall_fetch(whos, 2)
-	From worker 2:	                          Base  41762 KB     Module
-	From worker 2:	                          Core  27337 KB     Module
-	From worker 2:	                           Foo   2477 bytes  Module
-	From worker 2:	                          Main  46191 KB     Module
-	From worker 2:	                     gvar_self     13 bytes  String
+name          size summary
+––––––––– –––––––– –––––––
+Base               Module
+Core               Module
+Main               Module
+gvar_self 13 bytes String
 ```
 
 This does not apply to `function` or `type` declarations. However, anonymous functions bound to global

doc/src/manual/modules.md

@@ -119,7 +119,7 @@ end
 There are three important standard modules: Main, Core, and Base.
 
 Main is the top-level module, and Julia starts with Main set as the current module.  Variables
-defined at the prompt go in Main, and `whos()` lists variables in Main.
+defined at the prompt go in Main, and `varinfo()` lists variables in Main.
 
 Core contains all identifiers considered "built in" to the language, i.e. part of the core language
 and not libraries. Every module implicitly specifies `using Core`, since you can't do anything

doc/src/manual/parallel-computing.md

@@ -312,12 +312,13 @@ julia> let B = B
            remotecall_fetch(()->B, 2)
        end;
 
-julia> @spawnat 2 whos();
-
-julia>  From worker 2:                               A    800 bytes  10×10 Array{Float64,2}
-        From worker 2:                            Base               Module
-        From worker 2:                            Core               Module
-        From worker 2:                            Main               Module
+julia> @fetchfrom 2 varinfo()
+name           size summary
+––––––––– ––––––––– ––––––––––––––––––––––
+A         800 bytes 10×10 Array{Float64,2}
+Base                Module
+Core                Module
+Main                Module
 ```
 
 As can be seen, global variable `A` is defined on worker 2, but `B` is captured as a local variable

test/misc.jl

@@ -327,13 +327,16 @@ let R = Ref{Any}(nothing), depth = 10^6
     @test summarysize(R) == (depth + 4) * sizeof(Ptr)
 end
 
-module _test_whos_
+module _test_varinfo_
 export x
 x = 1.0
 end
-@test sprint(whos, Main, r"^$") == ""
-let v = sprint(whos, _test_whos_)
-    @test contains(v, "x      8 bytes  Float64")
+@test repr(varinfo(Main, r"^$")) == """
+| name | size | summary |
+|:---- | ----:|:------- |
+"""
+let v = repr(varinfo(_test_varinfo_))
+    @test contains(v, "| x              |   8 bytes | Float64 |")
 end
 
 # issue #13021
@@ -351,9 +354,9 @@ module Tmp14173
     export A
     A = randn(2000, 2000)
 end
-whos(IOBuffer(), Tmp14173) # warm up
+varinfo(Tmp14173) # warm up
 const MEMDEBUG = ccall(:jl_is_memdebug, Bool, ())
-@test @allocated(whos(IOBuffer(), Tmp14173)) < (MEMDEBUG ? 30000 : 10000)
+@test @allocated(varinfo(Tmp14173)) < (MEMDEBUG ? 60000 : 20000)
 
 ## test conversion from UTF-8 to UTF-16 (for Windows APIs)