change ordered keyword to dicttype keyword; this provides more flexib…

…ility, and avoids the pseudo-dependency on DataStructures that was causing precompile problems

README.md

@@ -52,15 +52,18 @@ json(a::Any)
 Returns a compact JSON representation as an `AbstractString`.
 
 ```julia
-JSON.parse(s::AbstractString; ordered=false)
-JSON.parse(io::IO; ordered=false)
-JSON.parsefile(filename::AbstractString; ordered=false, use_mmap=true)
+JSON.parse(s::AbstractString; dicttype=Dict)
+JSON.parse(io::IO; dicttype=Dict)
+JSON.parsefile(filename::AbstractString; dicttype=Dict, use_mmap=true)
 ```
 
 Parses a JSON `AbstractString` or IO stream into a nested Array or Dict.
 
-If `ordered=true` is specified, JSON objects are parsed into
-`OrderedDicts`, which maintains the insertion order of the items in
-the object. (*)
-
-(*) Requires the `DataStructures.jl` package to be installed.
+The `dicttype` indicates the dictionary type (`<: Associative`) that
+JSON objects are parsed to.  It defaults to `Dict` (the built-in Julia
+dictionary), but a different type can be passed to, for example,
+provide a desired ordering.  For example, if you `import DataStructures`
+(assuming the [DataStructures
+package](https://github.com/JuliaLang/DataStructures.jl) is
+installed), you can pass `dicttype=DataStructures.OrderedDict` to
+maintain the insertion order of the items in the object.

src/JSON.jl

@@ -253,7 +253,7 @@ function consumeString(io::IO, obj::IOBuffer)
     throw(EOFError())
 end
 
-function parse(io::IO; ordered::Bool=false)
+function parse{T<:Associative}(io::IO; dicttype::Type{T}=Dict)
     open_bracket = close_bracket = nothing
     try
         open_bracket, close_bracket = determine_bracket_type(io)
@@ -278,14 +278,14 @@ function parse(io::IO; ordered::Bool=false)
             consumeString(io, obj)
         end
     end
-    JSON.parse(takebuf_string(obj), ordered=ordered)
+    JSON.parse(takebuf_string(obj); dicttype=dicttype)
 end
 
-function parsefile(filename::AbstractString; ordered::Bool=false, use_mmap=true)
+function parsefile{T<:Associative}(filename::AbstractString; dicttype::Type{T}=Dict, use_mmap=true)
     sz = filesize(filename)
     open(filename) do io
         s = use_mmap ? UTF8String(Mmap.mmap(io, Vector{UInt8}, sz)) : readall(io)
-        JSON.parse(s, ordered=ordered)
+        JSON.parse(s; dicttype=dicttype)
     end
 end
 

src/Parser.jl

@@ -2,16 +2,6 @@ module Parser #JSON
 
 using Compat
 
-#Define ordered dictionary from DataStructures if present
-function __init__()
-    global _HAVE_DATASTRUCTURES = try
-        @eval import DataStructures.OrderedDict
-        true
-    catch
-        false
-    end
-end
-
 const TYPES = Any # Union{Dict, Array, AbstractString, Number, Bool, Void} # Types it may encounter
 const KEY_TYPES = AbstractString # Union{AbstractString} # Types it may encounter as object keys
 
@@ -77,13 +67,13 @@ end
 
 # PARSING
 
-function parse_array{T<:AbstractString}(ps::ParserState{T}, ordered::Bool)
+function parse_array{T<:AbstractString}(ps::ParserState{T}, dictT::Type)
     incr(ps) # Skip over the '['
     _array = TYPES[]
     chomp_space(ps)
     charat(ps)==']' && (incr(ps); return _array) # Check for empty array
     while true # Extract values from array
-        v = parse_value(ps, ordered) # Extract value
+        v = parse_value(ps, dictT) # Extract value
         push!(_array, v)
         # Eat up trailing whitespace
         chomp_space(ps)
@@ -101,23 +91,19 @@ function parse_array{T<:AbstractString}(ps::ParserState{T}, ordered::Bool)
     return _array
 end
 
-function parse_object{T<:AbstractString}(ps::ParserState{T}, ordered::Bool)
-    if ordered
-        parse_object(ps, ordered, OrderedDict{KEY_TYPES,TYPES}())
-    else
-        parse_object(ps, ordered, Dict{KEY_TYPES,TYPES}())
-    end
+function parse_object{T<:AbstractString}(ps::ParserState{T}, dictT::Type)
+    parse_object(ps, dictT, dictT{KEY_TYPES,TYPES}())
 end
 
-function parse_object{T<:AbstractString}(ps::ParserState{T}, ordered::Bool, obj)
+function parse_object{T<:AbstractString}(ps::ParserState{T}, dictT::Type, obj)
     incr(ps) # Skip over opening '{'
     chomp_space(ps)
     charat(ps)=='}' && (incr(ps); return obj) # Check for empty object
     while true
         chomp_space(ps)
         _key = parse_string(ps)           # Key
         skip_separator(ps)
-        _value = parse_value(ps, ordered) # Value
+        _value = parse_value(ps, dictT) # Value
         obj[_key] = _value                             # Building object
         chomp_space(ps)
         c = charat(ps) # Find the next pair or end of object
@@ -213,19 +199,19 @@ function parse_simple{T<:AbstractString}(ps::ParserState{T})
     ret
 end
 
-function parse_value{T<:AbstractString}(ps::ParserState{T}, ordered::Bool)
+function parse_value{T<:AbstractString}(ps::ParserState{T}, dictT::Type)
     chomp_space(ps)
     (ps.s > ps.e) && return nothing # Nothing left
 
     ch = charat(ps)
     if ch == '"'
         ret = parse_string(ps)
     elseif ch == '{'
-        ret = parse_object(ps, ordered)
+        ret = parse_object(ps, dictT)
     elseif (ch >= '0' && ch <= '9') || ch=='-' || ch=='+'
         ret = parse_number(ps)
     elseif ch == '['
-        ret = parse_array(ps, ordered)
+        ret = parse_array(ps, dictT)
     elseif ch == 'f' || ch == 't' || ch == 'n'
         ret = parse_simple(ps)
     else
@@ -315,12 +301,11 @@ function parse_number{T<:AbstractString}(ps::ParserState{T})
     end
 end
 
-function parse(str::AbstractString; ordered::Bool=false)
+function parse{T<:Associative}(str::AbstractString; dicttype::Type{T}=Dict)
     pos::Int = 1
     len::Int = endof(str)
     len < 1 && return
-    ordered && !_HAVE_DATASTRUCTURES && error("DataStructures package required for ordered parsing: try `Pkg.add(\"DataStructures\")`") 
-    parse_value(ParserState(str, pos, len), ordered)
+    parse_value(ParserState(str, pos, len), dicttype)
 end
 
 end #module Parser

test/runtests.jl

@@ -5,7 +5,7 @@ import DataStructures
 
 include(joinpath(dirname(@__FILE__),"json_samples.jl"))
 
-@test JSON.parse("{\"x\": 3}"; ordered = true) == DataStructures.OrderedDict{AbstractString,Any}([("x",3)])
+@test JSON.parse("{\"x\": 3}", dicttype=DataStructures.OrderedDict) == DataStructures.OrderedDict{AbstractString,Any}([("x",3)])
 
 # Test definitions -------
 validate_c(c) = begin