Add ArrayLength expression

src/back/glsl.rs

@@ -1042,6 +1042,10 @@ fn write_expression<'a, 'b>(
                     .join(","),
             ))
         }
+        Expression::ArrayLength(expr) => {
+            let base = write_expression(&builder.expressions[expr], module, builder)?;
+            Cow::Owned(format!("uint({}.length())", base))
+        }
     })
 }
 

src/lib.rs

@@ -635,6 +635,8 @@ pub enum Expression {
         origin: FunctionOrigin,
         arguments: Vec<Handle<Expression>>,
     },
+    /// Get dynamic array length.
+    ArrayLength(Handle<Expression>),
 }
 
 /// A code block is just a vector of statements.

src/proc/interface.rs

@@ -100,6 +100,9 @@ where
                     self.traverse_expr(argument);
                 }
             }
+            E::ArrayLength(expr) => {
+                self.traverse_expr(expr);
+            }
         }
     }
 

src/proc/typifier.rs

@@ -262,6 +262,10 @@ impl Typifier {
                     .ok_or(ResolveError::FunctionReturnsVoid)?;
                 Resolution::Handle(ty)
             }
+            crate::Expression::ArrayLength(_) => Resolution::Value(crate::TypeInner::Scalar {
+                kind: crate::ScalarKind::Uint,
+                width: 4,
+            }),
         })
     }