TransformerKit

A block-based API for NSValueTransformer, with a growing collection of useful examples.

NSValueTransformer, while perhaps obscure to most iOS programmers, remains a staple of OS X development. Before Objective-C APIs got in the habit of flinging block parameters hither and thither with reckless abandon, NSValueTransformer was the go-to way to encapsulate mutation functionality --- especially when it came to Bindings.

NSValueTransformer is convenient to use but a pain to set up. To create a value transformer you have to create a subclass, implement a handful of required methods, and register a singleton instance by name.

TransformerKit breathes new life into NSValueTransformer by making them dead-simple to define and register:

NSString * const TTTCapitalizedStringTransformerName = @"TTTCapitalizedStringTransformerName";

[NSValueTransformer registerValueTransformerWithName:TTTCapitalizedStringTransformerName
                               transformedValueClass:[NSString class]
                  returningTransformedValueWithBlock:^id(id value) {
  return [value capitalizedString];
}];

TransformerKit pairs nicely with InflectorKit and FormatterKit, providing well-designed APIs for manipulating user-facing content.

TransformerKit also contains a growing number of convenient transformers that your apps will love and cherish:

String Transformers

Capitalized
UPPERCASE
lowercase
CamelCase
llamaCase
snake_case
train-case
esreveR* (Reverse)
Rémövê Dîaçritics (Remove accents and combining marks)
ट्रांस्लितेराते स्ट्रिंग (Transliterate to Latin)
Any Valid ICU Transform*

Image Transformers

PNG Representation*
JPEG Representation*
GIF Representation (macOS)
TIFF Representation (macOS)

Date Transformers

ISO 8601 Timestamp*
RFC 2822 Timestamp*

JSON Data Transformers

JSON Transformer*

Data Transformers (macOS)

Base16 String Encode / Decode
Base32 String Encode / Decode
Base64 String Encode / Decode
Base85 String Encode / Decode

Cryptographic Transformers (macOS)

MD5, SHA-1, SHA-256, et al. Digests

* - Reversible

Contact

Mattt (@mattt)

License

TransformerKit is released under the MIT license. See the LICENSE file for more info.

mattt/TransformerKit