implement `or` function

1 files changed, 17 insertions, 0 deletions

diff --git a/src/makefile/functions.rs b/src/makefile/functions.rs
index 45ef925..9cd78f8 100644
--- a/src/makefile/functions.rs
+++ b/src/makefile/functions.rs
@@ -54,6 +54,10 @@ pub fn expand_call(
             assert!(args.len() == 2 || args.len() == 3);
             conditional::r#if(macros, &args[0], &args[1], args.get(2))
         }
+        "or" => {
+            assert!(!args.is_empty());
+            conditional::or(macros, args.iter())
+        }
         "and" => {
             assert!(!args.is_empty());
             conditional::and(macros, args.iter())
@@ -251,6 +255,19 @@ mod conditional {
         }
     }
 
+    pub fn or<'a>(
+        macros: &MacroSet,
+        args: impl Iterator<Item = &'a TokenString>,
+    ) -> Result<String> {
+        for arg in args {
+            let arg = macros.expand(arg)?;
+            if !arg.is_empty() {
+                return Ok(arg);
+            }
+        }
+        Ok(String::new())
+    }
+
     pub fn and<'a>(
         macros: &MacroSet,
         args: impl Iterator<Item = &'a TokenString>,