allow RMarkdown style chunk option passing:

e.g.:
- `julia, k1 = v1`
- `{julia, k1 = v1}`
- `julia k1 = v1`

src/reader/markdown.jl

@@ -5,7 +5,7 @@ function parse_markdown(document_body; is_pandoc = false)
         r"^<<(?<options>.*?)>>=\s*$",
         r"^@\s*$"
     else
-        r"^[`~]{3}(?:\{?)julia(?:;?)\s*(?<options>.*?)(\}|\s*)$",
+        r"^[`~]{3}(\{?)julia\s*([;,]?)\s*(?<options>.*?)(\}|\s*)$",
         r"^[`~]{3}\s*$"
     end
     return header, parse_markdown_body(document_body, code_start, code_end, offset)
@@ -55,22 +55,17 @@ function parse_markdown_body(document_body, code_start, code_end, offset)
     content = ""
     start_line = offset
 
-    options = Dict()
+    options = OptionDict()
     option_string = ""
+
     chunks = WeaveChunk[]
     for (line_no, line) in enumerate(lines)
         m = match(code_start, line)
         if !isnothing(m) && state === :doc
             state = :code
-            option_string = isnothing(m[:options]) ? "" : strip(m[:options])
 
-            options = Dict{Symbol,Any}()
-            if !isempty(option_string)
-                expr = Meta.parse(option_string)
-                Base.Meta.isexpr(expr, :(=)) && (options[expr.args[1]] = expr.args[2])
-                Base.Meta.isexpr(expr, :toplevel) &&
-                    map(pushopt, fill(options, length(expr.args)), expr.args)
-            end
+            option_string = isnothing(m[:options]) ? "" : strip(m[:options])
+            options = parse_options(option_string)
             haskey(options, :label) && (options[:name] = options[:label])
             haskey(options, :name) || (options[:name] = nothing)
 

src/reader/reader.jl

@@ -64,12 +64,6 @@ function parse_doc(document, informat)
         error("unsupported input format given: $informat")
 end
 
-function pushopt(options::Dict, expr::Expr)
-    if Base.Meta.isexpr(expr, :(=))
-        options[expr.args[1]] = expr.args[2]
-    end
-end
-
 # inline
 # ------
 
@@ -100,6 +94,34 @@ end
 
 parse_inline(str) = Inline[InlineText(str, 1)]
 
+# options
+# -------
+
+const OptionDict = Dict{Symbol,Any}
+
+function parse_options(str)::OptionDict
+    str = string('(', str, ')')
+    ex = Meta.parse(str)
+    nt = if Meta.isexpr(ex, (
+        :block, # "(k1 = v1; k2 = v2, ...)"
+        :tuple, # "(k1 = v1, k2 = v2, ...)"
+    ))
+        eval(Expr(:tuple, filter(is_valid_kv, ex.args)...))
+    elseif is_valid_kv(ex) # "(k = v)"
+        eval(Expr(:tuple, ex))
+    else
+        NamedTuple{}()
+    end
+    return dict(nt)
+end
+
+is_valid_kv(x) = Meta.isexpr(x, :(=))
+dict(nt) = Dict((k => v for (k,v) in zip(keys(nt), values(nt))))
+nt(dict) = NamedTuple{(Symbol.(keys(dict))...,)}((collect(values(dict))...,))
+
+# each input format
+# -----------------
+
 include("markdown.jl")
 include("script.jl")
 include("notebook.jl")

src/reader/script.jl

@@ -12,14 +12,14 @@ function parse_script(document_body)
     code_no = 0
     start_line = 1
 
-    options = Dict{Symbol,Any}()
+    options = OptionDict()
     option_string = ""
-    chunks = WeaveChunk[]
 
+    chunks = WeaveChunk[]
     for (line_no, line) in enumerate(lines)
         if (m = match(doc_line, line)) !== nothing && (m = match(opt_line, line)) === nothing
             line = replace(line, doc_start => "", count = 1)
-            startswith(line, ' ') && (line = line[2:end])
+            startswith(line, ' ') && (line = replace(line, ' ' => "", count = 1))
             if state === :code && !isempty(strip(content))
                 push!(chunks, CodeChunk(string('\n', strip(content)), code_no += 1, start_line, option_string, options))
                 content = ""
@@ -39,13 +39,7 @@ function parse_script(document_body)
             end
 
             option_string = replace(line, opt_start => "", count = 1)
-            options = Dict{Symbol,Any}()
-            if !isempty(option_string)
-                expr = Meta.parse(option_string)
-                Base.Meta.isexpr(expr, :(=)) && (options[expr.args[1]] = expr.args[2])
-                Base.Meta.isexpr(expr, :toplevel) &&
-                    map(pushopt, fill(options, length(expr.args)), expr.args)
-            end
+            options = parse_options(option_string)
             haskey(options, :label) && (options[:name] = options[:label])
             haskey(options, :name) || (options[:name] = nothing)
 

src/types.jl

@@ -47,7 +47,7 @@ function CodeChunk(content, number, start_line, optionstring, options)
         options,
         "",
         "",
-        AbstractStringString[],
+        AbstractString[],
         ChunkOutput[]
     )
 end