From e0a60ddc2cf3b2ccc3dff8e5af873b215cde7045 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Tue, 27 Aug 2019 11:58:32 -0300
Subject: [PATCH] add SlashEqual operator

---
 examples/hello.v |  1 +
 src/parser.zig   | 13 +++++++++++++
 src/scanner.zig  |  3 +++
 src/tokens.zig   |  1 +
 4 files changed, 18 insertions(+)

diff --git a/examples/hello.v b/examples/hello.v
index 55702b0..8b3f3bf 100644
--- a/examples/hello.v
+++ b/examples/hello.v
@@ -60,6 +60,7 @@ fn main(a int) int {
 	str.len += 1
 	str.len -= 1
 	str.len *= 1
+	str.len /= 1
 }
 
 fn (v Typ) voidfunc() {}
diff --git a/src/parser.zig b/src/parser.zig
index f510aab..12efaa5 100644
--- a/src/parser.zig
+++ b/src/parser.zig
@@ -703,6 +703,7 @@ pub const Parser = struct {
 
         if (self.compareAnyOf(&[_]TokenType{
             .ColonEqual, .Equal, .PlusEqual, .MinusEqual, .StarEqual,
+            .SlashEqual,
         })) {
             return try self.finishAssignment(expr, mutable);
         }
@@ -725,15 +726,27 @@ pub const Parser = struct {
             .PlusEqual => .Plus,
             .MinusEqual => .Minus,
             .StarEqual => .Star,
+            .SlashEqual => .Slash,
+
             else => unreachable,
         };
 
+        // we create new_lexeme so that
+        // the AST printer properly prints
+        //  x += 1
+        // as
+        //  (set x (+ x 1))
+        // and not
+        //  (set x (+= x 1))
         const new_lexeme: []const u8 = switch (op.ttype) {
             .ColonEqual => ":=",
             .Equal => "=",
+
             .PlusEqual => "+",
             .MinusEqual => "-",
             .StarEqual => "*",
+            .SlashEqual => "/",
+
             else => unreachable,
         };
 
diff --git a/src/scanner.zig b/src/scanner.zig
index 219203c..368efc5 100644
--- a/src/scanner.zig
+++ b/src/scanner.zig
@@ -315,7 +315,10 @@ pub const Scanner = struct {
 
             '/' => blk: {
                 var next = self.peekNext();
+
                 switch (next) {
+                    '=' => return self.makeToken(.SlashEqual),
+
                     '/' => blk2: {
                         while (self.peek() != '\n' and !self.isAtEnd()) {
                             _ = self.advance();
diff --git a/src/tokens.zig b/src/tokens.zig
index b8f2d1c..8ff6121 100644
--- a/src/tokens.zig
+++ b/src/tokens.zig
@@ -31,6 +31,7 @@ pub const TokenType = enum {
     MinusEqual,
     ColonEqual,
     StarEqual,
+    SlashEqual,
 
     // comparison ones
     EqualEqual,