From 8e9f827117ab1418578b692a2325754cc3ee692d Mon Sep 17 00:00:00 2001
From: Meghan Denny <hello@nektro.net>
Date: Tue, 27 Jul 2021 23:48:27 -0700
Subject: [PATCH] add optional max parameter to short circuit long string
 detection

---
 README.md   | 2 +-
 src/lib.zig | 7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index e8c53d2e9209c7d4118366258d444e120d21b209..f0e134bbf67b1c49d978cc4f053444fe8311cd7b 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ zigmod aq add 1/nektro/leven
 ```
 
 ## Usage
-`pub fn leven(comptime T: type, alloc: *std.mem.Allocator, a: []const T, b: []const T) !usize`
+`pub fn leven(comptime T: type, alloc: *std.mem.Allocator, a: []const T, b: []const T, max: ?usize) !usize`
 
 ## Future
 TODO Unicode support for strings
diff --git a/src/lib.zig b/src/lib.zig
index e45925436de7d27dfa14f0c65c8b19f1c9b6d3fa..c8fbb3196563e17ad8b7b11e27397db9a93b2dbf 100644
--- a/src/lib.zig
+++ b/src/lib.zig
@@ -15,7 +15,7 @@ const range = @import("range").range;
 //     );
 // }
 
-pub fn leven(comptime T: type, alloc: *std.mem.Allocator, a: []const T, b: []const T) !usize {
+pub fn leven(comptime T: type, alloc: *std.mem.Allocator, a: []const T, b: []const T, max: ?usize) !usize {
     if (std.mem.eql(T, a, b)) return 0;
 
     var left = a;
@@ -29,6 +29,10 @@ pub fn leven(comptime T: type, alloc: *std.mem.Allocator, a: []const T, b: []con
     var ll = left.len;
     var rl = right.len;
 
+    if (max != null and rl - ll >= max.?) {
+        return max.?;
+    }
+
     {
         const sl = suffixLen(T, a, b);
         ll -= sl;
@@ -67,6 +71,7 @@ pub fn leven(comptime T: type, alloc: *std.mem.Allocator, a: []const T, b: []con
         }
     }
 
+    if (max != null and result >= max.?) return max.?;
     return result;
 }
 
-- 
2.54.0