1 files changed, 87 insertions, 0 deletions
diff --git a/src/comp/front/pretty.rs b/src/comp/front/pretty.rs
new file mode 100644
index 00000000..2fd58126
--- /dev/null
+++ b/src/comp/front/pretty.rs
@@ -0,0 +1,87 @@
+import std._int;
+import std._str;
+import std._uint;
+import std._vec;
+
+export print_expr;
+
+// FIXME this is superseded by ../pretty/pprust.rs. can it be dropped?
+
+fn unknown() -> str {
+    ret "<unknown ast node>";
+}
+
+fn print_expr(@ast.expr expr) -> str {
+    alt (expr.node) {
+        case (ast.expr_lit(?lit, _)) {
+            ret print_lit(lit);
+        }
+        case (ast.expr_binary(?op, ?lhs, ?rhs, _)) {
+            ret print_expr_binary(op, lhs, rhs);
+        }
+        case (ast.expr_call(?path, ?args, _)) {
+            ret print_expr_call(path, args);
+        }
+        case (ast.expr_path(?path, _, _)) {
+            ret print_path(path);
+        }
+        case (_) {
+            ret unknown();
+        }
+    }
+}
+
+fn print_lit(@ast.lit lit) -> str {
+    alt (lit.node) {
+        case (ast.lit_str(?s)) {
+            ret "\"" + s + "\"";
+        }
+        case (ast.lit_int(?i)) {
+            ret _int.to_str(i, 10u);
+        }
+        case (ast.lit_uint(?u)) {
+            ret _uint.to_str(u, 10u);
+        }
+        case (_) {
+            ret unknown();
+        }
+    }
+}
+
+fn print_expr_binary(ast.binop op, @ast.expr lhs, @ast.expr rhs) -> str {
+    alt (op) {
+        case (ast.add) {
+            auto l = print_expr(lhs);
+            auto r = print_expr(rhs);
+            ret l + " + " + r;
+        }
+    }
+}
+
+fn print_expr_call(@ast.expr path_expr, vec[@ast.expr] args) -> str {
+    auto s = print_expr(path_expr);
+
+    s += "(";
+    fn print_expr_ref(&@ast.expr e) -> str { ret print_expr(e); }
+    auto mapfn = print_expr_ref;
+    auto argstrs = _vec.map[@ast.expr, str](mapfn, args);
+    s += _str.connect(argstrs, ", ");
+    s += ")";
+
+    ret s;
+}
+
+fn print_path(ast.path path) -> str {
+    ret _str.connect(path.node.idents, ".");
+}
+
+//
+// Local Variables:
+// mode: rust
+// fill-column: 78;
+// indent-tabs-mode: nil
+// c-basic-offset: 4
+// buffer-file-coding-system: utf-8-unix
+// compile-command: "make -k -C ../.. 2>&1 | sed -e 's/\\/x\\//x:\\//g'";
+// End:
+//