ffi: new native function format

parser/src/main/kotlin/gay/pizza/pork/parser/Parser.kt

@@ -308,8 +308,11 @@ class Parser(source: TokenSource, attribution: NodeAttribution) :
   override fun parseNative(): Native = guarded(NodeType.Native) {
     expect(TokenType.Native)
     val form = parseSymbol()
-    val definition = parseStringLiteral()
-    Native(form, definition)
+    val definitions = mutableListOf<StringLiteral>()
+    while (peek(TokenType.StringLiteral)) {
+      definitions.add(parseStringLiteral())
+    }
+    Native(form, definitions)
   }
 
   override fun parseNoneLiteral(): NoneLiteral = guarded(NodeType.NoneLiteral) {

parser/src/main/kotlin/gay/pizza/pork/parser/Printer.kt

@@ -82,7 +82,12 @@ class Printer(buffer: StringBuilder) : NodeVisitor<Unit> {
     append("native ")
     visit(node.form)
     append(" ")
-    visit(node.definition)
+    for ((index, argument) in node.definitions.withIndex()) {
+      visit(argument)
+      if (index + 1 != node.definitions.size) {
+        append(" ")
+      }
+    }
   }
 
   override fun visitNoneLiteral(node: NoneLiteral) {