From 5338635618df080f42374460fa25f56b5299cbc0 Mon Sep 17 00:00:00 2001
From: Michael Hatherly <michaelhatherly@gmail.com>
Date: Thu, 25 Feb 2016 10:57:35 +0200
Subject: [PATCH] Remove `at-init` from docsystem.

Replaces macro init with a function instead. Appears to reduce the
amount of code generated by `at-doc` which should help shorten
bootstrapping time slightly.

Also changes the name of the `ObjectIdDict` used to store docstrings
to a gensym'd one to avoid naming clashes. `Docs.meta` has always
been available to access this const without needing to know it's
name so this shouldn't be a major breaking change.
---
 base/docs/Docs.jl      | 32 ++++++++++++--------------------
 base/docs/bootstrap.jl |  2 +-
 base/loading.jl        |  2 +-
 3 files changed, 14 insertions(+), 22 deletions(-)

diff --git a/base/docs/Docs.jl b/base/docs/Docs.jl
index 12ff28e9d882e..b9ebeae41b531 100644
--- a/base/docs/Docs.jl
+++ b/base/docs/Docs.jl
@@ -65,23 +65,16 @@ export doc
 # Basic API / Storage
 
 const modules = Module[]
+const META    = gensym(:meta)
 
-const META′ = :__META__
+meta(m::Module = current_module()) = isdefined(m, META) ? getfield(m, META) : ObjectIdDict()
 
-meta(mod) = mod.(META′)
-
-meta() = meta(current_module())
-
-macro init()
-    META = esc(META′)
-    quote
-        if !isdefined($(Expr(:quote, META′)))
-            const $META = ObjectIdDict()
-            doc!($META, @doc_str $("Documentation metadata for `$(current_module())`."))
-            push!(modules, current_module())
-            nothing
-        end
+function initmeta(m::Module = current_module())
+    if !isdefined(m, META)
+        eval(m, :(const $META = $(ObjectIdDict())))
+        push!(modules, m)
     end
+    nothing
 end
 
 "`doc!(obj, data)`: Associate the metadata `data` with `obj`."
@@ -447,7 +440,6 @@ end
 
 function namedoc(meta, def, def′)
     quote
-        @init
         $(esc(def))
         doc!($(esc(namify(def′))), $(mdify(meta)))
         nothing
@@ -457,7 +449,6 @@ end
 function funcdoc(meta, def, def′)
     f = esc(namify(def′))
     quote
-        @init
         $(esc(def))
         doc!($f, $(esc(signature(def′))), $(mdify(meta)), $(esc(quot(def′))))
         $f
@@ -466,7 +457,6 @@ end
 
 function typedoc(meta, def, def′)
     quote
-        @init
         $(esc(def))
         doc!($(esc(namify(def′))), $(mdify(meta)), $(field_meta(unblock(def′))))
         nothing
@@ -492,7 +482,6 @@ end
 
 function vardoc(meta, def, name)
     quote
-        @init
         $(esc(def))
         doc!(@var($(esc(namify(name)))), $(mdify(meta)))
     end
@@ -584,6 +573,9 @@ function docm(meta, ex, define = true)
     # otherwise calling `loaddocs` would redefine all documented functions and types.
     def = define ? x : nothing
 
+    # Initalise the module's docstring storage.
+    initmeta()
+
     # Method / macro definitions and "call" syntax.
     #
     #   function f(...) ... end
@@ -629,7 +621,7 @@ function docm(meta, ex, define = true)
 
     # All other expressions are undocumentable and should be handled on a case-by-case basis
     # with `@__doc__`. Unbound string literals are also undocumentable since they cannot be
-    # retrieved from the `__META__` `ObjectIdDict` without a reference to the string.
+    # retrieved from the module's metadata `ObjectIdDict` without a reference to the string.
     docerror(ex)
 end
 
@@ -666,7 +658,7 @@ Base.DocBootstrap.setexpand!(docm)
 
 # Names are resolved relative to the Base module, so inject the ones we need there.
 
-eval(Base, :(import .Docs: @init, @var, doc!, doc, @doc_str))
+eval(Base, :(import .Docs: @var, doc!, doc, @doc_str))
 
 Base.DocBootstrap.loaddocs()
 
diff --git a/base/docs/bootstrap.jl b/base/docs/bootstrap.jl
index 4295bb756ddfd..f6c8d2e522aa9 100644
--- a/base/docs/bootstrap.jl
+++ b/base/docs/bootstrap.jl
@@ -48,7 +48,7 @@ DocBootstrap
 """
     loaddocs()
 
-Move all docstrings from `DocBootstrap.docs` to their module's `__META__` dict.
+Move all docstrings from `DocBootstrap.docs` to their module's metadata dict.
 """
 function loaddocs()
     node = docs
diff --git a/base/loading.jl b/base/loading.jl
index b3b3faf05b6ce..8b522437c03cc 100644
--- a/base/loading.jl
+++ b/base/loading.jl
@@ -171,7 +171,7 @@ function _require_from_serialized(node::Int, mod::Symbol, path_to_try::ByteStrin
 
     if restored !== nothing
         for M in restored
-            if isdefined(M, :__META__)
+            if isdefined(M, Base.Docs.META)
                 push!(Base.Docs.modules, M)
             end
         end