mollusk 0e4acfb8f2 fix incorrect folder name for julia-0.6.x
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2018-06-11 03:28:36 -07:00

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# This file is a part of Julia. License is MIT: https://julialang.org/license
"""
Docs
The `Docs` module provides the `@doc` macro which can be used to set and retrieve
documentation metadata for Julia objects.
Please see the manual section on documentation for more
information.
"""
module Docs
"""
# Documentation
Functions, methods and types can be documented by placing a string before the definition:
\"""
# The Foo Function
`foo(x)`: Foo the living hell out of `x`.
\"""
foo(x) = ...
The `@doc` macro can be used directly to both set and retrieve documentation / metadata. By
default, documentation is written as Markdown, but any object can be placed before the
arrow. For example:
@doc "blah" ->
function foo() ...
The `->` is not required if the object is on the same line, e.g.
@doc "foo" foo
## Documenting objects after they are defined
You can document an object after its definition by
@doc "foo" function_to_doc
@doc "bar" TypeToDoc
For macros, the syntax is `@doc "macro doc" :(@Module.macro)` or `@doc "macro doc"
:(string_macro"")` for string macros. Without the quote `:()` the expansion of the macro
will be documented.
## Retrieving Documentation
You can retrieve docs for functions, macros and other objects as follows:
@doc foo
@doc @time
@doc md""
## Functions & Methods
Placing documentation before a method definition (e.g. `function foo() ...` or `foo() = ...`)
will cause that specific method to be documented, as opposed to the whole function. Method
docs are concatenated together in the order they were defined to provide docs for the
function.
"""
:(Core.@doc)
include("bindings.jl")
import Base.Markdown: @doc_str, MD
import Base.Meta: quot, isexpr
import Base: Callable
import ..CoreDocs: lazy_iterpolate
export doc
# Basic API / Storage
const modules = Module[]
const META = gensym(:meta)
meta(m::Module = current_module()) = isdefined(m, META) ? getfield(m, META) : ObjectIdDict()
function initmeta(m::Module = current_module())
if !isdefined(m, META)
eval(m, :(const $META = $(ObjectIdDict())))
push!(modules, m)
end
nothing
end
function signature!(tv, expr::Expr)
if isexpr(expr, (:call, :macrocall))
sig = :(Union{Tuple{}})
for arg in expr.args[2:end]
isexpr(arg, :parameters) && continue
if isexpr(arg, :kw) # optional arg
push!(sig.args, :(Tuple{$(sig.args[end].args[2:end]...)}))
end
push!(sig.args[end].args, argtype(arg))
end
if isexpr(expr.args[1], :curly) && isempty(tv)
append!(tv, tvar.(expr.args[1].args[2:end]))
end
for i = length(tv):-1:1
push!(sig.args, :(Tuple{$(tv[i].args[1])}))
end
for i = length(tv):-1:1
sig = Expr(:where, sig, tv[i])
end
sig
elseif isexpr(expr, :where)
append!(tv, tvar.(expr.args[2:end]))
signature!(tv, expr.args[1])
else
signature!(tv, expr.args[1])
end
end
signature!(tv, other) = :(Union{})
signature(expr::Expr) = signature!([], expr)
signature(other) = signature!([], other)
function argtype(expr::Expr)
isexpr(expr, :(::)) && return expr.args[end]
isexpr(expr, :(...)) && return :(Vararg{$(argtype(expr.args[1]))})
argtype(expr.args[1])
end
argtype(other) = :Any
tvar(x::Expr) = x
tvar(s::Symbol) = :($s <: Any)
# Docsystem types.
# ================
"""
Docs.DocStr
Stores the contents of a single docstring as well as related metadata.
Both the raw text, `.text`, and the parsed markdown, `.object`, are tracked by this type.
Parsing of the raw text is done lazily when a request is made to render the docstring,
which helps to reduce total precompiled image size.
The `.data` fields stores several values related to the docstring, such as: path,
linenumber, source code, and fielddocs.
"""
mutable struct DocStr
text :: Core.SimpleVector
object :: Nullable
data :: Dict{Symbol, Any}
end
function docstr(binding::Binding, typesig::ANY = Union{})
for m in modules
dict = meta(m)
if haskey(dict, binding)
docs = dict[binding].docs
if haskey(docs, typesig)
return docs[typesig]
end
end
end
error("could not find matching docstring for '$binding :: $typesig'.")
end
docstr(object, data = Dict()) = _docstr(object, data)
_docstr(vec::Core.SimpleVector, data) = DocStr(vec, Nullable(), data)
_docstr(str::AbstractString, data) = DocStr(Core.svec(str), Nullable(), data)
_docstr(object, data) = DocStr(Core.svec(), Nullable(object), data)
_docstr(doc::DocStr, data) = (doc.data = merge(data, doc.data); doc)
macro ref(x)
binding = bindingexpr(namify(x))
typesig = signature(x)
esc(docexpr(binding, typesig))
end
docexpr(args...) = Expr(:call, docstr, args...)
function formatdoc(d::DocStr)
buffer = IOBuffer()
for part in d.text
formatdoc(buffer, d, part)
end
Markdown.parse(seekstart(buffer))
end
@noinline formatdoc(buffer, d, part) = print(buffer, part)
function parsedoc(d::DocStr)
if isnull(d.object)
md = formatdoc(d)
md.meta[:module] = d.data[:module]
md.meta[:path] = d.data[:path]
d.object = Nullable(md)
end
get(d.object)
end
"""
MultiDoc
Stores a collection of docstrings for related objects, ie. a `Function`/`DataType` and
associated `Method` objects.
Each documented object in a `MultiDoc` is referred to by it's signature which is represented
by a `Union` of `Tuple` types. For example the following `Method` definition
f(x, y) = ...
is stored as `Tuple{Any, Any}` in the `MultiDoc` while
f{T}(x::T, y = ?) = ...
is stored as `Union{Tuple{T, Any}, Tuple{T}} where T`.
Note: The `Function`/`DataType` object's signature is always `Union{}`.
"""
mutable struct MultiDoc
"Ordered (via definition order) vector of object signatures."
order::Vector{Type}
"Documentation for each object. Keys are signatures."
docs::ObjectIdDict
MultiDoc() = new(Type[], ObjectIdDict())
end
# Docstring registration.
# =======================
"""
Docs.doc!(binding, str, sig)
Adds a new docstring `str` to the docsystem for `binding` and signature `sig`.
"""
function doc!(b::Binding, str::DocStr, sig::ANY = Union{})
initmeta()
m = get!(meta(), b, MultiDoc())
if haskey(m.docs, sig)
# We allow for docstrings to be updated, but print a warning since it is possible
# that over-writing a docstring *may* have been accidental. The warning
# is suppressed for symbols in Main, for interactive use (#23011).
current_module() == Main || warn("replacing docs for '$b :: $sig' in module '$(current_module())'.")
else
# The ordering of docstrings for each Binding is defined by the order in which they
# are initially added. Replacing a specific docstring does not change it's ordering.
push!(m.order, sig)
end
m.docs[sig] = str
str.data[:binding] = b
str.data[:typesig] = sig
return b
end
# Docstring lookup.
# =================
"""
getdoc(obj)
getdoc(obj, sig)
Return a custom docstring object associated with the object `obj` and, optionally, the tuple
type signature `sig`. See `MultiDoc` docs for an explanation of the possible values of `sig`.
The returned object can either be a markdown object generated by `Markdown.parse` or some
other custom type used to display non-markdown formatted documentation.
A return value of `nothing` can be used to signify to the docsystem that no documentation
was found for `obj`, in which case the docsystem will fall back to searching for the
`Binding` associated with `obj` instead.
"""
function getdoc end
getdoc(x, sig) = getdoc(x)
getdoc(x) = nothing
"""
Docs.doc(binding, sig)
Returns all documentation that matches both `binding` and `sig`.
If `getdoc` returns a non-`nothing` result on the value of the binding, then a
dynamic docstring is returned instead of one based on the binding itself.
"""
function doc(binding::Binding, sig::Type = Union{})
if defined(binding)
result = getdoc(resolve(binding), sig)
result === nothing || return result
end
results, groups = DocStr[], MultiDoc[]
# Lookup `binding` and `sig` for matches in all modules of the docsystem.
for mod in modules
dict = meta(mod)
if haskey(dict, binding)
multidoc = dict[binding]
push!(groups, multidoc)
for msig in multidoc.order
sig <: msig && push!(results, multidoc.docs[msig])
end
end
end
if isempty(groups)
# When no `MultiDoc`s are found that match `binding` then we check whether `binding`
# is an alias of some other `Binding`. When it is we then re-run `doc` with that
# `Binding`, otherwise if it's not an alias then we generate a summary for the
# `binding` and display that to the user instead.
alias = aliasof(binding)
alias == binding ? summarize(alias, sig) : doc(alias, sig)
else
# There was at least one match for `binding` while searching. If there weren't any
# matches for `sig` then we concatenate *all* the docs from the matching `Binding`s.
if isempty(results)
for group in groups, each in group.order
push!(results, group.docs[each])
end
end
# Get parsed docs and concatenate them.
md = catdoc(map(parsedoc, results)...)
# Save metadata in the generated markdown.
if isa(md, Markdown.MD)
md.meta[:results] = results
md.meta[:binding] = binding
md.meta[:typesig] = sig
end
return md
end
end
# Some additional convenience `doc` methods that take objects rather than `Binding`s.
doc(obj::UnionAll) = doc(Base.unwrap_unionall(obj))
doc(object, sig::Type = Union{}) = doc(aliasof(object, typeof(object)), sig)
doc(object, sig...) = doc(object, Tuple{sig...})
"""
Docs.fielddoc(binding, field)
Returns documentation for a particular `field` of a type if it exists.
"""
function fielddoc(binding::Binding, field::Symbol)
for mod in modules
dict = meta(mod)
if haskey(dict, binding)
multidoc = dict[binding]
if haskey(multidoc.docs, Union{})
fields = multidoc.docs[Union{}].data[:fields]
if haskey(fields, field)
doc = fields[field]
return isa(doc, Markdown.MD) ? doc : Markdown.parse(doc)
end
end
end
end
fields = join(["`$f`" for f in fieldnames(resolve(binding))], ", ", ", and ")
fields = isempty(fields) ? "no fields" : "fields $fields"
Markdown.parse("`$(resolve(binding))` has $fields.")
end
# As with the additional `doc` methods, this converts an object to a `Binding` first.
fielddoc(object, field::Symbol) = fielddoc(aliasof(object, typeof(object)), field)
# Object Summaries.
# =================
function summarize(binding::Binding, sig)
io = IOBuffer()
println(io, "No documentation found.\n")
if defined(binding)
summarize(io, resolve(binding), binding)
else
println(io, "Binding `", binding, "` does not exist.")
end
md = Markdown.parse(seekstart(io))
# Save metadata in the generated markdown.
md.meta[:results] = DocStr[]
md.meta[:binding] = binding
md.meta[:typesig] = sig
return md
end
function summarize(io::IO, λ::Function, binding)
kind = startswith(string(binding.var), '@') ? "macro" : "`Function`"
println(io, "`", binding, "` is a ", kind, ".")
println(io, "```\n", methods(λ), "\n```")
end
function summarize(io::IO, T::DataType, binding)
println(io, "**Summary:**")
println(io, "```")
println(io,
T.abstract ? "abstract type" :
T.mutable ? "mutable struct" :
Base.isstructtype(T) ? "struct" : "primitive type",
" ", T, " <: ", supertype(T)
)
println(io, "```")
if !isempty(fieldnames(T))
println(io, "**Fields:**")
println(io, "```")
pad = maximum(length(string(f)) for f in fieldnames(T))
for (f, t) in zip(fieldnames(T), T.types)
println(io, rpad(f, pad), " :: ", t)
end
println(io, "```")
end
if !isempty(subtypes(T))
println(io, "**Subtypes:**")
println(io, "```")
for t in subtypes(T)
println(io, t)
end
println(io, "```")
end
end
function summarize(io::IO, m::Module, binding)
readme = Pkg.dir(string(m), "README.md")
if isfile(readme)
println(io, "Displaying the `README.md` for the module instead.\n")
println(io, "---\n")
println(io, readstring(readme))
else
println(io, "No docstring or `README.md` found for module `", m, "`.\n")
end
end
function summarize{T}(io::IO, ::T, binding)
println(io, "`", binding, "` is of type `", T, "`.\n")
summarize(io, T, binding)
end
# Utilities.
# ==========
"""
`catdoc(xs...)`: Combine the documentation metadata `xs` into a single meta object.
"""
catdoc() = nothing
catdoc(xs...) = vcat(xs...)
const keywords = Dict{Symbol, DocStr}()
isdoc(s::AbstractString) = true
isdoc(x) = isexpr(x, :string) ||
(isexpr(x, :macrocall) && x.args[1] === Symbol("@doc_str")) ||
(isexpr(x, :call) && x.args[1] === Base.Markdown.doc_str)
function unblock(ex)
isexpr(ex, :block) || return ex
exs = filter(ex -> !(isa(ex, LineNumberNode) || isexpr(ex, :line)), ex.args)
length(exs) == 1 || return ex
return unblock(exs[1])
end
uncurly(ex) = isexpr(ex, :curly) ? ex.args[1] : ex
namify(x) = nameof(x, isexpr(x, :macro))
function nameof(x::Expr, ismacro)
if isexpr(x, :.)
ismacro ? macroname(x) : x
else
n = isexpr(x, (:module, :type, :bitstype)) ? 2 : 1
nameof(x.args[n], ismacro)
end
end
nameof(q::QuoteNode, ismacro) = nameof(q.value, ismacro)
nameof(s::Symbol, ismacro) = ismacro ? macroname(s) : s
nameof(other, ismacro) = other
macroname(s::Symbol) = Symbol('@', s)
macroname(x::Expr) = Expr(x.head, x.args[1], macroname(x.args[end].value))
isfield(x) = isexpr(x, :.) &&
(isa(x.args[1], Symbol) || isfield(x.args[1])) &&
(isa(x.args[2], QuoteNode) || isexpr(x.args[2], :quote))
# @doc expression builders.
# =========================
"""
Docs.metadata(expr)
Build a `Dict` expression containing metadata captured from the expression `expr`.
Fields that may be included in the returned `Dict`:
- `:path`: String representing the file where `expr` is defined.
- `:linenumber`: Linenumber where `expr` is defined.
- `:module`: Module where the docstring is defined.
- `:fields`: `Dict` of all field docs found in `expr`. Only for concrete types.
"""
function metadata(expr)
args = []
# Filename and linenumber of the docstring.
push!(args, :($(Pair)(:path, $(Base).@__FILE__)))
push!(args, :($(Pair)(:linenumber, $(unsafe_load(cglobal(:jl_lineno, Cint))))))
# Module in which the docstring is defined.
push!(args, :($(Pair)(:module, $(current_module)())))
# Field docs for concrete types.
if isexpr(expr, :type)
fields = []
tmp = nothing
for each in expr.args[3].args
if isdoc(each)
tmp = each
elseif tmp !== nothing && (isa(each, Symbol) || isexpr(each, :(::)))
push!(fields, (namify(each), tmp))
tmp = nothing
end
end
dict = :($(Dict)($([:($(Pair)($(quot(f)), $d)) for (f, d) in fields]...)))
push!(args, :($(Pair)(:fields, $dict)))
end
:($(Dict)($(args...)))
end
function keyworddoc(str, def)
docstr = esc(docexpr(lazy_iterpolate(str), metadata(def)))
:($(keywords)[$(esc(quot(def.name)))] = $docstr)
end
function objectdoc(str, def, expr, sig = :(Union{}))
binding = esc(bindingexpr(namify(expr)))
docstr = esc(docexpr(lazy_iterpolate(str), metadata(expr)))
quote
$(esc(def))
$(doc!)($binding, $docstr, $(esc(sig)))
end
end
function calldoc(str, def)
args = def.args[2:end]
if isempty(args) || all(validcall, args)
objectdoc(str, nothing, def, signature(def))
else
docerror(def)
end
end
validcall(x) = isa(x, Symbol) || isexpr(x, (:(::), :..., :kw, :parameters))
function moduledoc(meta, def, def)
name = namify(def)
docex = Expr(:call, doc!, bindingexpr(name),
docexpr(lazy_iterpolate(meta), metadata(name))
)
if def === nothing
esc(:(eval($name, $(quot(docex)))))
else
def = unblock(def)
block = def.args[3].args
if !def.args[1]
isempty(block) && error("empty baremodules are not documentable.")
insert!(block, 2, :(import Base: @doc))
end
push!(block, docex)
esc(Expr(:toplevel, def))
end
end
# Shares a single doc, `meta`, between several expressions from the tuple expression `ex`.
function multidoc(meta, ex, define)
out = Expr(:toplevel)
str = docexpr(lazy_iterpolate(meta), metadata(ex))
ref = Ref{DocStr}()
for (n, arg) in enumerate(ex.args)
# The first `arg` to be documented needs to also create the docstring for the group.
# Subsequent `arg`s just need `ref` to be able to find the docstring without having
# to create an entirely new one each.
docstr = n === 1 ? :($(ref)[] = $str) : :($(ref)[])
push!(out.args, :(@doc($docstr, $arg, $define)))
end
esc(out)
end
"""
@__doc__(ex)
Low-level macro used to mark expressions returned by a macro that should be documented. If
more than one expression is marked then the same docstring is applied to each expression.
macro example(f)
quote
\$(f)() = 0
@__doc__ \$(f)(x) = 1
\$(f)(x, y) = 2
end |> esc
end
`@__doc__` has no effect when a macro that uses it is not documented.
"""
:(Core.@__doc__)
function __doc__!(meta, def, define)
# Two cases must be handled here to avoid redefining all definitions contained in `def`:
if define
# `def` has not been defined yet (this is the common case, i.e. when not generating
# the Base image). We just need to convert each `@__doc__` marker to an `@doc`.
finddoc(def) do each
each.head = :macrocall
each.args = [Symbol("@doc"), meta, each.args[end], define]
end
else
# `def` has already been defined during Base image gen so we just need to find and
# document any subexpressions marked with `@__doc__`.
docs = []
found = finddoc(def) do each
push!(docs, :(@doc($meta, $(each.args[end]), $define)))
end
# If any subexpressions have been documented then replace the entire expression with
# just those documented subexpressions to avoid redefining any definitions.
if found
def.head = :toplevel
def.args = docs
end
found
end
end
# Walk expression tree `def` and call `λ` when any `@__doc__` markers are found. Returns
# `true` to signify that at least one `@__doc__` has been found, and `false` otherwise.
function finddoc(λ, def::Expr)
if isexpr(def, :block, 2) && isexpr(def.args[1], :meta, 1) && def.args[1].args[1] === :doc
# Found the macroexpansion of an `@__doc__` expression.
λ(def)
true
else
found = false
for each in def.args
found |= finddoc(λ, each)
end
found
end
end
finddoc(λ, def) = false
# Predicates and helpers for `docm` expression selection:
const FUNC_HEADS = [:function, :stagedfunction, :macro, :(=)]
const BINDING_HEADS = [:typealias, :const, :global, :(=)] # deprecation: remove `typealias` post-0.6
# For the special `:@mac` / `:(Base.@mac)` syntax for documenting a macro after definition.
isquotedmacrocall(x) =
isexpr(x, :copyast, 1) &&
isa(x.args[1], QuoteNode) &&
isexpr(x.args[1].value, :macrocall, 1)
# Simple expressions / atoms the may be documented.
isbasicdoc(x) = isexpr(x, :.) || isa(x, Union{QuoteNode, Symbol})
is_signature(x) = isexpr(x, :call) || (isexpr(x, :(::), 2) && isexpr(x.args[1], :call)) || isexpr(x, :where)
function docm(meta, ex, define = true)
# Some documented expressions may be decorated with macro calls which obscure the actual
# expression. Expand the macro calls and remove extra blocks.
x = unblock(macroexpand(ex))
# Don't try to redefine expressions. This is only needed for `Base` img gen since
# otherwise calling `loaddocs` would redefine all documented functions and types.
def = define ? x : nothing
if isa(x, GlobalRef) && (x::GlobalRef).mod == current_module()
x = (x::GlobalRef).name
end
# Keywords using the `@kw_str` macro in `base/docs/basedocs.jl`.
#
# "..."
# kw"if", kw"else"
#
isa(x, Base.BaseDocs.Keyword) ? keyworddoc(meta, x) :
# Method / macro definitions and "call" syntax.
#
# function f(...) ... end
# f(...) = ...
# macro m(...) end
# function f end
# f(...)
#
isexpr(x, FUNC_HEADS) && is_signature(x.args[1]) ? objectdoc(meta, def, x, signature(x)) :
isexpr(x, :function) && !isexpr(x.args[1], :call) ? objectdoc(meta, def, x) :
isexpr(x, :call) ? calldoc(meta, x) :
# Type definitions.
#
# type T ... end
# abstract T
# bitstype N T
#
isexpr(x, [:type, :abstract, :bitstype]) ? objectdoc(meta, def, x) :
# "Bindings". Names that resolve to objects with different names, ie.
#
# const T = S
# T = S
# global T = S
#
isexpr(x, BINDING_HEADS) && !isexpr(x.args[1], :call) ? objectdoc(meta, def, x) :
# Quoted macrocall syntax. `:@time` / `:(Base.@time)`.
isquotedmacrocall(x) ? objectdoc(meta, def, x) :
# Modules and baremodules.
isexpr(x, :module) ? moduledoc(meta, def, x) :
# Document several expressions with the same docstring. `a, b, c`.
isexpr(x, :tuple) ? multidoc(meta, x, define) :
# Errors generated by calling `macroexpand` are passed back to the call site.
isexpr(x, :error) ? esc(x) :
# When documenting macro-generated code we look for embedded `@__doc__` calls.
__doc__!(meta, x, define) ? esc(x) :
# Any "basic" expression such as a bare function or module name or numeric literal.
isbasicdoc(x) ? objectdoc(meta, nothing, x) :
# 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 module's metadata `ObjectIdDict` without a reference to the string.
docerror(ex)
end
function docerror(ex)
txt = """
cannot document the following expression:
$(isa(ex, AbstractString) ? repr(ex) : ex)"""
if isexpr(ex, :macrocall)
txt *= "\n\n'$(ex.args[1])' not documentable. See 'Base.@__doc__' docs for details."
end
:($(error)($txt, "\n"))
end
function docm(ex)
if isexpr(ex, :->)
docm(ex.args...)
elseif haskey(keywords, ex)
parsedoc(keywords[ex])
elseif isa(ex, Union{Expr, Symbol})
binding = esc(bindingexpr(namify(ex)))
if isexpr(ex, [:call, :macrocall])
sig = esc(signature(ex))
:($(doc)($binding, $sig))
else
:($(doc)($binding))
end
else
:($(doc)($(typeof)($(esc(ex)))))
end
end
# MD support
catdoc(md::MD...) = MD(md...)
include("utils.jl")
# Swap out the bootstrap macro with the real one.
Core.atdoc!(docm)
function loaddocs(docs)
for (mod, ex, str, file, line) in docs
data = Dict(:path => string(file), :linenumber => line)
doc = docstr(str, data)
eval(mod, :(@doc($doc, $ex, false)))
end
empty!(docs)
end
end