Application Context Implementation #4
| @ -286,6 +286,43 @@ pub const Writer = struct { | ||||
|     } | ||||
| }; | ||||
| 
 | ||||
| /// | ||||
| /// Returns `true` if `this_bytes` is the same length and contains the same data as `that_bytes`, | ||||
| /// otherwise `false`. | ||||
| /// | ||||
| pub fn equalsBytes(this_bytes: []const u8, that_bytes: []const u8) bool { | ||||
|     return std.mem.eql(u8, this_bytes, that_bytes); | ||||
| } | ||||
| 
 | ||||
| test "Equivalence of bytes" { | ||||
|     const bytes_sequence = &.{69, 42, 0}; | ||||
|     const testing = std.testing; | ||||
| 
 | ||||
|     try testing.expect(equalsBytes(bytes_sequence, bytes_sequence)); | ||||
|     try testing.expect(!equalsBytes(bytes_sequence, &.{69, 42})); | ||||
| } | ||||
| 
 | ||||
| /// | ||||
| /// Returns a deterministic hash code compiled from each byte in `bytes`. | ||||
| /// | ||||
| /// **Note** that this operation has `O(n)` time complexity. | ||||
| /// | ||||
| pub fn hashBytes(bytes: []const u8) usize { | ||||
|     var hash = @as(usize, 5381); | ||||
| 
 | ||||
|     for (bytes) |byte| hash = ((hash << 5) + hash) + byte; | ||||
| 
 | ||||
|     return hash; | ||||
| } | ||||
| 
 | ||||
| test "Hashing bytes" { | ||||
|     const bytes_sequence = &.{69, 42, 0}; | ||||
|     const testing = std.testing; | ||||
| 
 | ||||
|     try testing.expect(hashBytes(bytes_sequence) == hashBytes(bytes_sequence)); | ||||
|     try testing.expect(hashBytes(bytes_sequence) != hashBytes(&.{69, 42})); | ||||
| } | ||||
| 
 | ||||
| /// | ||||
| /// Writer that silently throws consumed data away and never fails. | ||||
| /// | ||||
|  | ||||
| @ -173,35 +173,14 @@ pub fn KeyContext(comptime Key: type) type { | ||||
|     }; | ||||
| } | ||||
| 
 | ||||
| /// | ||||
| /// Tests if the contents of `this_string` lexically equals the contents of `that_string`. | ||||
| /// | ||||
| fn equalsString(this_string: []const u8, that_string: []const u8) bool { | ||||
|     return std.mem.eql(u8, this_string, that_string); | ||||
| } | ||||
| 
 | ||||
| /// | ||||
| /// Hashes `string` into a hash value of `usize`. | ||||
| /// | ||||
| fn hashString(string: []const u8) usize { | ||||
|     var hash = @as(usize, 5381); | ||||
| 
 | ||||
|     for (string) |byte| hash = ((hash << 5) + hash) + byte; | ||||
| 
 | ||||
|     return hash; | ||||
| } | ||||
| 
 | ||||
| /// | ||||
| /// A [KeyContext] for handling `[]const u8` types. | ||||
| /// | ||||
| pub const string_context = KeyContext([]const u8){ | ||||
|     .hash = hashString, | ||||
|     .equals = equalsString, | ||||
| }; | ||||
| 
 | ||||
| test "Hashed table manipulation with string context" { | ||||
| test "Hashed table manipulation with bytes context" { | ||||
|     const testing = std.testing; | ||||
|     var table = try Hashed([]const u8, u32, string_context).init(testing.allocator); | ||||
|     const io = @import("./io.zig"); | ||||
| 
 | ||||
|     var table = try Hashed([]const u8, u32, .{ | ||||
|         .equals = io.equalsBytes, | ||||
|         .hash = io.hashBytes, | ||||
|     }).init(testing.allocator); | ||||
| 
 | ||||
|     defer table.deinit(); | ||||
| 
 | ||||
|  | ||||
| @ -1,29 +0,0 @@ | ||||
| const std = @import("std"); | ||||
| const table = @import("./table.zig"); | ||||
| 
 | ||||
| /// | ||||
| /// Tests if the contents of `this_utf8_sequence` lexically equals the contents of | ||||
| /// `that_utf8_sequence`. | ||||
| /// | ||||
| pub fn equals(this_utf8_sequence: []const u8, that_utf8_sequence: []const u8) bool { | ||||
|     return std.mem.eql(u8, this_utf8_sequence, that_utf8_sequence); | ||||
| } | ||||
| 
 | ||||
| /// | ||||
| /// Returns a deterministic hash for `utf8_sequence`. | ||||
| /// | ||||
| pub fn hash(utf8_sequence: []const u8) usize { | ||||
|     var utf8_hash = @as(usize, 5381); | ||||
| 
 | ||||
|     for (utf8_sequence) |utf8_code| utf8_hash = ((utf8_hash << 5) + utf8_hash) + utf8_code; | ||||
| 
 | ||||
|     return utf8_hash; | ||||
| } | ||||
| 
 | ||||
| /// | ||||
| /// A [table.KeyContext] for handling UTF-8 character sequences. | ||||
| /// | ||||
| pub const key_context = table.KeyContext([]const u8){ | ||||
|     .hash = hash, | ||||
|     .equals = equals, | ||||
| }; | ||||
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