lib: intro Text::split_once_on

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>

diff --git a/lib/standard/string_search.nit b/lib/standard/string_search.nit
index 8dcf90a..0786ec9 100644 (file)
--- a/lib/standard/string_search.nit
+++ b/lib/standard/string_search.nit
@@ -355,6 +355,17 @@ redef class Text
        # @deprecated alias for `split`
        fun split_with(p: Pattern): Array[SELFTYPE] do return self.split(p)
 
+       # Split `self` on the first `=`
+       #
+       #     assert "hello".split_once_on('l') == ["he", "lo"]
+       #     assert "a, b, c, d, e".split_once_on(", ") == ["a", "b, c, d, e"]
+       fun split_once_on(p: Pattern): Array[SELFTYPE]
+       do
+               var m = p.search_in(self, 0)
+               if m == null then return [self]
+               return new Array[SELFTYPE].with_items(substring(0, m.from), substring_from(m.after))
+       end
+
        # Replace all occurences of a pattern with a string
        #
        #     assert "hlelo".replace("le", "el")             ==  "hello"