Combined str_matches and str_match and added start parameter.

strings.scad

@@ -219,35 +219,53 @@ function _str_cmp_recurse(str,sindex,pattern,plen,pindex=0,) =
 
 // Function: str_match()
 // Usage:
-//   str_match(str,pattern)
+//   str_match(str,pattern,[last],[all],[start])
 // Description:
-//   Searches input string `str` for the string `pattern` and returns the index of the first or last match in `str`. 
+//   Searches input string `str` for the string `pattern` and returns the index or indices of the matches in `str`.  
-//   If `pattern` is empty then it returns 0.  If `pattern` doesn't match it returns undef.
+//   By default str_match() returns the index of the first match in `str`.  If `last` is true then it returns the index of the last match.
+//   If the pattern is the empty string the first match is at zero and the last match is the last character of the `str`.
+//   If `start` is set then the search begins at index start, working either forward and backward from that position.  If you set `start`
+//   and `last` is true then the search will find the pattern if it begins at index `start`.  If no match exists, returns undef. 
+//   If you set `all` to true then all str_match() returns all of the matches in a list, or an empty list if there are no matches.  
 // Arguments:
 //   str = string to search
 //   pattern = string pattern to search for
 //   last = set to true to return the last match. Default: false
+//   all = set to true to return all matches as a list.  Overrides last.  Default: false  
+//   start = index where the search starts
 // Example:
 //   str_match("abc123def123abc","123");   // Returns 3
 //   str_match("abc123def123abc","b");     // Returns 1
 //   str_match("abc123def123abc","1234");  // Returns undef
 //   str_match("abc","");                  // Returns 0
-//   str_match("abc123def123abc","123",last=true);   // Returns 9
+//   str_match("abc123def123", "123", start=4);     // Returns 9
-//   str_match("abc123def123abc","b",last=true);     // Returns 13
+//   str_match("abc123def123abc","123",last=true);  // Returns 9
-//   str_match("abc123def123abc","1234",last=true);  // Returns undef
+//   str_match("abc123def123abc","b",last=true);    // Returns 13
-//   str_match("abc","",last=true);                  // Returns 2
+//   str_match("abc123def123abc","1234",last=true); // Returns undef
-function str_match(str,pattern,last=false) =
+//   str_match("abc","",last=true);                 // Returns 2
-                                 pattern=="" ? (last?len(str)-1:0) :
+//   str_match("abc123def123", "123", start=8, last=true));  // Returns 3
-                                  last ? _str_match_last(str,pattern,len(str)-len(pattern)) :
+//   str_match("abc123def123abc","123",all=true);   // Returns [3,9]
-                                         _str_match(str,pattern,len(str)-len(pattern));
+//   str_match("abc123def123abc","b",all=true);     // Returns [1,13]
+//   str_match("abc123def123abc","1234",all=true);  // Returns []
+//   str_match("abc","",all=true);                  // Returns [0,1,2]
+function str_match(str,pattern,start=undef,last=false,all=false) =
+                                 all ? _str_matches(str,pattern) :
+                                 let( start = first_defined([start,last?len(str)-len(pattern):0]))
+                                 pattern=="" ? start :
+                                 last ? _str_match_last(str,pattern,start) :
+                                         _str_match(str,pattern,len(str)-len(pattern),start);
 
-function _str_match(str,pattern,max_sindex,sindex=0) = 
+function _str_match(str,pattern,max_sindex,sindex) = 
   sindex<=max_sindex && !_str_cmp(str,sindex, pattern) ? _str_match(str,pattern,max_sindex,sindex+1) :
                                                         (sindex <= max_sindex ? sindex : undef);
-
 function _str_match_last(str,pattern,sindex) = 
   sindex>=0 && !_str_cmp(str,sindex, pattern) ? _str_match_last(str,pattern,sindex-1) :
                                                         (sindex >=0 ? sindex : undef);
+function _str_matches(str,pattern) =
+   pattern == "" ? list_range(len(str)) :
+   [for(i=[0:1:len(str)-len(pattern)]) if (_str_cmp(str,i,pattern)) i];
+
+
 // Function: str_matches()
 // Usage:
 //   str_matches(str,pattern)
@@ -258,13 +276,6 @@ function _str_match_last(str,pattern,sindex) =
 //   str = string to search
 //   pattern = string pattern to search for
 // Example:
-//   str_matches("abc123def123abc","123");   // Returns [3,9]
-//   str_matches("abc123def123abc","b");     // Returns [1,13]
-//   str_matches("abc123def123abc","1234");  // Returns []
-//   str_matches("abc","");                  // Returns [0,1,2]
-function str_matches(str,pattern) =
-   pattern == "" ? list_range(len(str)) :
-   [for(i=[0:1:len(str)-len(pattern)]) if (_str_cmp(str,i,pattern)) i];
 
 
 // Function: starts_with()