Merge branch 'with-meta'

Supersedes and closes JuliaLang#1755.
Closes JuliaLang#1576.

base/exports.jl

@@ -14,7 +14,8 @@ export
  Pkg,
  Operators,
  Errno,
-
+ Meta,
+
 # Types
  AbstractMatrix,
  AbstractSparseMatrix,

base/meta.jl

@@ -0,0 +1,47 @@
+module Meta
+#
+# convenience functions for metaprogramming
+#
+
+export quot, 
+ isexpr, 
+ show_sexpr
+
+quot(ex) = expr(:quote, {ex})
+
+isexpr(ex::Expr, head) = ex.head === head
+isexpr(ex::Expr, heads::Set) = has(heads, ex.head)
+isexpr(ex::Expr, heads::Vector) = contains(heads, ex.head)
+isexpr(ex, head) = false
+
+isexpr(ex, head, n::Int) = isexpr(ex, head) && length(ex.args) == n
+
+
+# ---- show_sexpr: print an AST as an S-expression ----
+
+show_sexpr(ex) = show_sexpr(OUTPUT_STREAM, ex)
+show_sexpr(io::IO, ex) = show_sexpr(io, ex, 0)
+show_sexpr(io::IO, ex, indent::Int) = show(io, ex)
+
+const sexpr_indent_width = 2
+
+function show_sexpr(io::IO, ex::QuoteNode, indent::Int)
+ inner = indent + sexpr_indent_width
+ print(io, "(:quote, #QuoteNode\n", " "^inner)
+ show_sexpr(io, ex.value, inner)
+ print(io, '\n', " "^indent, ')')
+end
+function show_sexpr(io::IO, ex::Expr, indent::Int)
+ inner = indent + sexpr_indent_width
+ print(io, '(')
+ show_sexpr(io, ex.head, inner)
+ for arg in ex.args
+ print(io, ex.head === :block ? ",\n"*" "^inner : ", ")
+ show_sexpr(io, arg, inner)
+ end
+ if length(ex.args) == 0; print(io, ",)")
+ else print(io, (ex.head === :block ? "\n"*" "^indent : ""), ')')
+ end
+end
+
+end # module

base/sysimg.jl

@@ -140,12 +140,13 @@ include("combinatorics.jl")
 include("darray2.jl")
 include("mmap.jl")
 
-# utilities - version, timing, help, edit
+# utilities - version, timing, help, edit, metaprogramming
 include("version.jl")
 include("datafmt.jl")
 include("deepcopy.jl")
 include("util.jl")
 include("test.jl")
+include("meta.jl")
 
 # linear algebra
 include("blas.jl")