Commit 95e66a915b
Changed files (1)
lib
std
lib/std/mem.zig
@@ -991,6 +991,40 @@ test "mem.count" {
testing.expect(count(u8, "owowowu", "owowu") == 1);
}
+/// Returns true if the haystack contains expected_count or more needles
+/// needle.len must be > 0
+/// does not count overlapping needles
+pub fn containsAtLeast(comptime T: type, haystack: []const T, expected_count: usize, needle: []const T) bool {
+ assert(needle.len > 0);
+ if (expected_count == 0) return true;
+
+ var i: usize = 0;
+ var found: usize = 0;
+
+ while (indexOfPos(T, haystack, i, needle)) |idx| {
+ i = idx + needle.len;
+ found += 1;
+ if (found == expected_count) return true;
+ }
+ return false;
+}
+
+test "mem.containsAtLeast" {
+ testing.expect(containsAtLeast(u8, "aa", 0, "a"));
+ testing.expect(containsAtLeast(u8, "aa", 1, "a"));
+ testing.expect(containsAtLeast(u8, "aa", 2, "a"));
+ testing.expect(!containsAtLeast(u8, "aa", 3, "a"));
+
+ testing.expect(containsAtLeast(u8, "radaradar", 1, "radar"));
+ testing.expect(!containsAtLeast(u8, "radaradar", 2, "radar"));
+
+ testing.expect(containsAtLeast(u8, "radarradaradarradar", 3, "radar"));
+ testing.expect(!containsAtLeast(u8, "radarradaradarradar", 4, "radar"));
+
+ testing.expect(containsAtLeast(u8, " radar radar ", 2, "radar"));
+ testing.expect(!containsAtLeast(u8, " radar radar ", 3, "radar"));
+}
+
/// Reads an integer from memory with size equal to bytes.len.
/// T specifies the return type, which must be large enough to store
/// the result.