Change string.trimCharacters to specify different leading and trailin…

…g trim sets

lib/string.cpp

@@ -92,11 +92,11 @@ std::vector<utf8string> splitLines(const utf8string &ss)
     return r;
 }
 
-utf8string trimCharacters(const utf8string &ss, const utf8string &trimChars)
+utf8string trimCharacters(const utf8string &ss, const utf8string &trimLeadingChars, const utf8string &trimTrailingChars)
 {
     const std::string &s = ss.str(); // TODO: utf8
-    std::string::size_type first = s.find_first_not_of(trimChars.str());
-    std::string::size_type last = s.find_last_not_of(trimChars.str());
+    std::string::size_type first = s.find_first_not_of(trimLeadingChars.str());
+    std::string::size_type last = s.find_last_not_of(trimTrailingChars.str());
     if (first == std::string::npos || last == std::string::npos) {
         return utf8string("");
     }

lib/string.neon

@@ -106,15 +106,15 @@ DECLARE NATIVE FUNCTION splitLines(s: String): Array<String>
  |
  |  Trim given characters from the start and end of a string.
  |%
-DECLARE NATIVE FUNCTION trimCharacters(s: String, trimChars: String): String
+DECLARE NATIVE FUNCTION trimCharacters(s: String, trimLeadingChars, trimTrailingChars: String): String
 
 %|
  |  Function: trim
  |
  |  Trim spaces from the start and end of a string.
  |%
 FUNCTION trim(s: String): String
-    RETURN trimCharacters(s, " ")
+    RETURN trimCharacters(s, " ", " ")
 END FUNCTION
 
 %|

t/string-test.neon

@@ -27,10 +27,16 @@ ASSERT string.splitLines("a\nb") = ["a", "b"]
 ASSERT string.splitLines("a\nb\n") = ["a", "b"]
 ASSERT string.splitLines("hello\nworld\r\neverybody\n") = ["hello", "world", "everybody"]
 
-print(string.trimCharacters("  Hello World  ", " "))
+print(string.trimCharacters("  Hello World  ", " ", " "))
 %= Hello World
 
-print(string.trimCharacters(" ", " "))
+print(string.trimCharacters("  Hello World  ", " ", ""))
+%= Hello World  
+
+print(string.trimCharacters("  Hello World  ", "", " "))
+%=   Hello World
+
+print(string.trimCharacters(" ", " ", " "))
 %= 
 
 print(string.upper("Hello World"))

tools/helium.py

@@ -2650,8 +2650,8 @@ def neon_string_splitLines(env, s):
     s = re.sub("\n$", "", s, 1)
     return s.split("\n")
 
-def neon_string_trimCharacters(env, s, t):
-    return s.strip(t)
+def neon_string_trimCharacters(env, s, leading, trailing):
+    return s.lstrip(leading).rstrip(trailing)
 
 def neon_string_upper(env, s):
     return s.upper()