Implement split_each

eval/builtins.go

@@ -30,7 +30,7 @@ func CoreDict() *data.Dictionary {
 			">":      data.NewProc(greaterThan),
 			"<=":     data.NewProc(lessThanOrEq),
 			">=":     data.NewProc(greaterThanOrEq),
-			"length": data.NewProc(length), // push length of the quotation or string on top of the stack
+			"length": data.NewProc(length), // pop a quotation or string and push its length
 
 			// BOOLEANS
 			"true":  data.NewBoolean(true),  // TRUE literal
@@ -286,10 +286,9 @@ func then(d *data.Dictionary, s *data.Stack) error {
 
 // Quotation manipulation.
 
-// length returns the length of the quotation on top of the stack without
-// popping it.
+// length pops a quotation or string and pushes its length.
 func length(d *data.Dictionary, s *data.Stack) error {
-	val, err := s.Peek()
+	val, err := s.Pop()
 	if err != nil {
 		return err
 	}
@@ -458,11 +457,10 @@ func find(d *data.Dictionary, s *data.Stack) error {
 	if err != nil {
 		return err
 	}
-	str, err := s.PeekType(data.String)
+	str, err := s.PopType(data.String)
 	if err != nil {
 		return err
 	}
-	s.Push(substr)
 	s.Push(data.NewNumber(float64(strings.Index(str.Str, substr.Str))))
 	return nil
 }

interpret/basics_test.go

@@ -88,11 +88,11 @@ var basicTestCases = []interpretTestCase{
 		[]string{`
 			{ -- Not tail recursive, could have bad performance?
 				"f" let
-				length "l" let
+				dup length "l" let
 				{
 					lop 
 					f apply
-					{f each}  length 0 = not  then apply
+					{f each}  dup length 0 = not  then apply
 				} l 0 = not then apply
 			} "each" define
 			{1 2 3} {say} each 

interpret/prelude.naiveconcat

@@ -18,11 +18,11 @@
 -- Not tail recursive, could have bad performance
 {
     "f" let
-    length "l" let
+    dup length "l" let
     {
         lop 
         f apply
-        {f each}  length 0 = not  then apply
+        {f each}  dup length 0 = not  then apply
     } l 0 = not   then apply
 } "each" define
 
@@ -33,10 +33,10 @@
 {
   "f" let
   "accumulator" let
-  length "l" let
+  dup length "l" let
   {
     lop "x" let
-    length "next_l" let
+    dup length "next_l" let
     accumulator x f apply
     {f reduce} {swap drop} next_l 0 = not if  
   } l 0 = not then apply
@@ -58,25 +58,60 @@
 -- STRINGS
 
 
+{ split swap drop } "trim_front" define
+-- > "Foobar" 2 trim_front
+-- ["obar"]
+
+{ find 0 >= } "has_substring?" define
+-- > "Brendan" "end" has_substring?
+-- [ TRUE ]
+
 {
-  find "index" let
   "delimiter" let
   "original" let
+  delimiter length "delimiter_length" let
 
   { 
+    original delimiter find "index" let
     original index split  -- split before the delimiter
-    delimiter length swap drop  -- drop the delimiter
-    split swap drop
-    swap {} append append  -- quote the two values
+    delimiter_length trim_front  -- drop the delimiter
+    "second part" let
+    "first part" let
+    {} first_part append second_part append
   } 
-  { original {} append } 
-  index 0 >= if 
+  { {} original append } 
+  original delimiter has_substring? if
 
 } "split_on" define
 
 
+{
+  "delimiter" let
+  "original" let
+  delimiter length "delimiter_length" let
+
+  { 
+    original delimiter find "index" let
+    original index split  -- split before the delimiter
+    delimiter_length trim_front -- drop the delimiter
+    "second part" let
+    "first part" let
+    {} first_part append 
+    second_part
+    { -- split_each the second part and concat the result
+      delimiter split_each concat
+    }
+    { -- or just append the second part if no more splits necessary
+      append
+    }
+    second_part delimiter has_substring? if
+  } 
+  { {} original append } 
+  original delimiter has_substring? if
+} "split_each" define
+
 
 -- CONCAT
 
 
-{ swap {append} reduce } "concat" define
+{ swap { append } reduce } "concat" define

parse/lexer.go

@@ -8,11 +8,11 @@ import (
 )
 
 const (
-	wordRunes            = "abcdefghijjklmnopqrstuvwxyz+-*/=_><" // wordRunes are legal characters in a word name.
-	stringDelimiter rune = '"'                                   // delimiter that opens or closes a string.
-	stringEscaper   rune = '\\'                                  // delimiter that escapes the following character in a string.
-	quotationOpener rune = '{'                                   // delimiter that opens a quotation.
-	quotationCloser rune = '}'                                   // delimiter that closes a quotation.
+	wordRunes            = "abcdefghijjklmnopqrstuvwxyz+-*/=_><?" // wordRunes are legal characters in a word name.
+	stringDelimiter rune = '"'                                    // delimiter that opens or closes a string.
+	stringEscaper   rune = '\\'                                   // delimiter that escapes the following character in a string.
+	quotationOpener rune = '{'                                    // delimiter that opens a quotation.
+	quotationCloser rune = '}'                                    // delimiter that closes a quotation.
 )
 
 // Lexer scans an input src and emits a stream of lexed tokens.