2 files changed, 57 insertions, 12 deletions

diff --git a/src/comp/front/ast.rs b/src/comp/front/ast.rs
index c74e1620..48ba9187 100644
--- a/src/comp/front/ast.rs
+++ b/src/comp/front/ast.rs
@@ -1,7 +1,10 @@
 
-import std.util.option;
+import util.common.option;
 import std.map.hashmap;
 import util.common.span;
+import util.common.option;
+import util.common.some;
+import util.common.none;
 
 type ident = str;
 
@@ -40,10 +43,10 @@ tag unop {
 }
 
 tag stmt {
-    stmt_block(block);
     stmt_decl(@decl);
     stmt_ret(option[@expr]);
     stmt_log(@expr);
+    stmt_expr(@expr);
 }
 
 tag decl {
@@ -63,6 +66,8 @@ tag expr {
     expr_field(@expr, ident);
     expr_index(@expr, @expr);
     expr_cast(@expr, ty);
+    expr_if(@expr, block, option[block]);
+    expr_block(block);
 }
 
 tag lit {
diff --git a/src/comp/front/parser.rs b/src/comp/front/parser.rs
index 44bddf08..12a1f072 100644
--- a/src/comp/front/parser.rs
+++ b/src/comp/front/parser.rs
@@ -2,15 +2,9 @@ import std._io;
 import driver.session;
 import util.common;
 import util.common.new_str_hash;
-
-// FIXME: import std.util.option and use it here.
-// import std.util.option;
-
-tag option[T] {
-  none;
-  some(T);
-}
-
+import util.common.option;
+import util.common.some;
+import util.common.none;
 
 state type parser =
     state obj {
@@ -414,8 +408,35 @@ io fn parse_or_expr(parser p) -> @ast.expr {
     ret parse_binary_exprs(p, sub, vec(tup(token.OROR, ast.or)));
 }
 
+io fn parse_if_expr(parser p) -> @ast.expr {
+    expect(p, token.IF);
+    expect(p, token.LPAREN);
+    auto cond = parse_expr(p);
+    expect(p, token.RPAREN);
+    auto thn = parse_block(p);
+    let option[ast.block] els = none[ast.block];
+    alt (p.peek()) {
+        case (token.ELSE) {
+            p.bump();
+            els = some(parse_block(p));
+        }
+    }
+    ret @ast.expr_if(cond, thn, els);
+}
+
 io fn parse_expr(parser p) -> @ast.expr {
-    ret parse_or_expr(p);
+    alt (p.peek()) {
+        case (token.LBRACE) {
+            ret @ast.expr_block(parse_block(p));
+        }
+        case (token.IF) {
+            ret parse_if_expr(p);
+        }
+        case (_) {
+            ret parse_or_expr(p);
+        }
+
+    }
 }
 
 io fn parse_stmt(parser p) -> @ast.stmt {
@@ -426,6 +447,25 @@ io fn parse_stmt(parser p) -> @ast.stmt {
             expect(p, token.SEMI);
             ret @ast.stmt_log(e);
         }
+
+        // Handle the (few) block-expr stmts first.
+
+        case (token.IF) {
+            ret @ast.stmt_expr(parse_expr(p));
+        }
+
+        case (token.LBRACE) {
+            ret @ast.stmt_expr(parse_expr(p));
+        }
+
+
+        // Remainder are line-expr stmts.
+
+        case (_) {
+            auto e = parse_expr(p);
+            expect(p, token.SEMI);
+            ret @ast.stmt_expr(e);
+        }
     }
     p.err("expected statement");
     fail;