Remove eval dependency from unicode.syntax

basis/unicode/syntax/syntax.factor

@@ -2,7 +2,7 @@
 ! See http://factorcode.org/license.txt for BSD license.
 USING: unicode.data kernel math sequences parser lexer
 bit-arrays namespaces make sequences.private arrays quotations
-assocs classes.predicate math.order eval ;
+assocs classes.predicate math.order strings.parser ;
 IN: unicode.syntax
 
 ! Character classes (categories)
@@ -26,7 +26,7 @@ IN: unicode.syntax
     categories [ swap member? ] with map >bit-array ;
 
 : as-string ( strings -- bit-array )
-    concat "\"" tuck 3append eval ;
+    concat unescape-string ;
 
 : [category] ( categories -- quot )
     [

core/strings/parser/parser-tests.factor

@@ -0,0 +1,4 @@
+IN: strings.parser.tests
+USING: strings.parser tools.test ;
+
+[ "Hello\n\rworld" ] [ "Hello\\n\\rworld" unescape-string ] unit-test

core/strings/parser/parser.factor

@@ -58,3 +58,15 @@ name>char-hook global [
     lexer get [
         [ swap tail-slice (parse-string) ] "" make swap
     ] change-lexer-column ;
+
+: (unescape-string) ( str -- str' )
+    dup [ CHAR: \\ = ] find [
+        cut-slice [ % ] dip rest-slice
+        next-escape [ , ] dip
+        (unescape-string)
+    ] [
+        drop %
+    ] if ;
+
+: unescape-string ( str -- str' )
+    [ (unescape-string) ] "" make ;