char: add is_lowercase(), is_uppercase()

src/libcore/char.rs

@@ -41,6 +41,26 @@ import is_alphabetic = unicode::derived_property::Alphabetic;
 import is_XID_start = unicode::derived_property::XID_Start;
 import is_XID_continue = unicode::derived_property::XID_Continue;
 
+/*
+Function: is_lowercase
+
+Indicates whether a character is in lower case, defined in terms of the
+Unicode General Category 'Ll'.
+*/
+pure fn is_lowercase(c: char) -> bool {
+    ret unicode::general_category::Ll(c);
+}
+
+/*
+Function: is_uppercase
+
+Indicates whether a character is in upper case, defined in terms of the
+Unicode General Category 'Lu'.
+*/
+pure fn is_uppercase(c: char) -> bool {
+    ret unicode::general_category::Lu(c);
+}
+
 /*
 Function: is_whitespace
 

src/test/stdtest/char.rs

@@ -3,6 +3,24 @@ import core::*;
 use std;
 import char;
 
+#[test]
+fn test_is_lowercase() {
+    assert char::is_lowercase('a');
+    assert char::is_lowercase('ö');
+    assert char::is_lowercase('ß');
+    assert !char::is_lowercase('Ü');
+    assert !char::is_lowercase('P');
+}
+
+#[test]
+fn test_is_uppercase() {
+    assert !char::is_uppercase('h');
+    assert !char::is_uppercase('ä');
+    assert !char::is_uppercase('ß');
+    assert char::is_uppercase('Ö');
+    assert char::is_uppercase('T');
+}
+
 #[test]
 fn test_is_whitespace() {
     assert char::is_whitespace(' ');