1 files changed, 25 insertions, 0 deletions
diff --git a/doc/macros.txt b/doc/macros.txt
new file mode 100644
index 0000000..f39a30b
--- /dev/null
+++ b/doc/macros.txt
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+/*
+ * dollar sign identifiers are only valid within a macro body (what i believe
+ * scheme folk call "hygienic")
+ */
+
+macro SWAP($a, $b) {
+	let $tmp = $a
+	$a := b
+	$b := $tmp
+}
+
+proc foo(n ^Node) {
+	SWAP(&n^.in.data[0], &n^.in.data[1])
+}
+
+/*
+ * note that the macro body between the braces isn't a new scope, so you can
+ * still e.g. have a macro that defines a variable.  or, perhaps, a function:
+ */
+
+macro V2OP($name, $op) {
+	func $name(a, b vec2) vec2 {
+		return vec2 { a.x $op b.x, a.y $op b.y }
+	}
+}