h1: make | operator work with anything other than syntactic calls (in which case it just calls the value)

in case you call a function to get a function, parenthesise it

    1 | getFunction ()   -- getFunction 1 ()
    1 | (getFunction ()) -- (getFunction ()) 1

crates/haku/src/compiler.rs

@@ -460,14 +460,8 @@ fn compile_pipe_call<'a>(
     left: NodeId,
     call: NodeId,
 ) -> CompileResult {
-    if src.ast.kind(call) != NodeKind::Call {
+    match src.ast.kind(call) {
-        c.emit(Diagnostic::error(
+        NodeKind::Call => {
-            src.ast.span(call),
-            "the right side of a pipe `|` must be a function call",
-        ));
-        return Ok(());
-    }
-
             let mut walk = src.ast.walk(call);
             let Some(func) = walk.node() else {
                 return Ok(());
@@ -489,6 +483,12 @@ fn compile_pipe_call<'a>(
             });
 
             emit_nary_call(c, src, func, argument_count)?;
+        }
+        _ => {
+            compile_expr(c, src, left)?;
+            emit_nary_call(c, src, call, 1)?;
+        }
+    }
 
     Ok(())
 }