Lower- and uppercase string conversion functions

2 files changed, 12 insertions, 0 deletions

diff --git a/src/library/mod.rs b/src/library/mod.rs
index a549aa72..d02c9608 100644
--- a/src/library/mod.rs
+++ b/src/library/mod.rs
@@ -63,6 +63,8 @@ pub fn new() -> Scope {
     std.def_func("rgb", rgb);
     std.def_func("min", min);
     std.def_func("max", max);
+    std.def_func("lower", lower);
+    std.def_func("upper", upper);
 
     // Colors.
     std.def_const("white", RgbaColor::WHITE);
diff --git a/src/library/utility.rs b/src/library/utility.rs
index 84f1d7ab..b26ed154 100644
--- a/src/library/utility.rs
+++ b/src/library/utility.rs
@@ -75,3 +75,13 @@ fn minmax(args: &mut Arguments, goal: Ordering) -> TypResult<Value> {
     }
     Ok(extremum)
 }
+
+/// `lower`: Convert a string to lowercase.
+pub fn lower(_: &mut EvalContext, args: &mut Arguments) -> TypResult<Value> {
+    Ok(args.expect::<Str>("string")?.to_lowercase().into())
+}
+
+/// `upper`: Convert a string to uppercase.
+pub fn upper(_: &mut EvalContext, args: &mut Arguments) -> TypResult<Value> {
+    Ok(args.expect::<Str>("string")?.to_uppercase().into())
+}