start moving parse helpers to moonscript

moonscript/parse.lua

@@ -8,6 +8,7 @@ local util = require"moonscript.util"
 local data = require"moonscript.data"
 local types = require"moonscript.types"
 local literals = require "moonscript.parse.literals"
+local parse_util = require "moonscript.parse.util"
 
 local ntype = types.ntype
 local trim = util.trim
@@ -37,23 +38,9 @@ local Shebang = literals.Shebang
 local Name = Space * _Name
 Num = Space * (Num / function(value) return {"number", value} end)
 
-local function count_indent(str)
-	local sum = 0
-	for v in str:gmatch("[\t ]") do
-		if v == ' ' then sum = sum + 1 end
-		if v == '\t' then sum = sum + 4 end
-	end
-	return sum
-end
-
-local Indent = C(S"\t "^0) / count_indent
-
--- can't have P(false) because it causes preceding patterns not to run
-local Cut = P(function() return false end)
-
-local function ensure(patt, finally)
-	return patt * finally + finally * Cut
-end
+local Indent = parse_util.Indent
+local Cut = parse_util.Cut
+local ensure = parse_util.ensure
 
 local function extract_line(str, start_pos)
 	str = str:sub(start_pos)

moonscript/parse/util.lua

@@ -0,0 +1,31 @@
+local P, C, S
+do
+  local _obj_0 = require("lpeg")
+  P, C, S = _obj_0.P, _obj_0.C, _obj_0.S
+end
+local Indent = C(S("\t ") ^ 0) / function(str)
+  do
+    local sum = 0
+    for v in str:gmatch("[\t ]") do
+      local _exp_0 = v
+      if " " == _exp_0 then
+        sum = sum + 1
+      elseif "\t" == _exp_0 then
+        sum = sum + 4
+      end
+    end
+    return sum
+  end
+end
+local Cut = P(function()
+  return false
+end)
+local ensure
+ensure = function(patt, finally)
+  return patt * finally + finally * Cut
+end
+return {
+  Indent = Indent,
+  Cut = Cut,
+  ensure = ensure
+}

moonscript/parse/util.moon

@@ -0,0 +1,23 @@
+
+import P, C, S from require "lpeg"
+
+-- captures an indentation, returns indent depth
+Indent = C(S"\t "^0) / (str) ->
+  with sum = 0
+    for v in str\gmatch "[\t ]"
+      switch v
+        when " "
+          sum += 1
+        when "\t"
+          sum += 4
+
+
+-- causes pattern in progress to be rejected
+-- can't have P(false) because it causes preceding patterns not to run
+Cut = P -> false
+
+-- ensures finally runs regardless of whether pattern fails or passes
+ensure = (patt, finally) ->
+	patt * finally + finally * Cut
+
+{ :Indent, :Cut, :ensure }