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[Typia] 15,000x faster TypeScript Validator and its histories

Jeongho Nam on December 18, 2022

Renamed to Typia https://github.com/samchon/typia Hello, I'm developer of typescript-json typia. In nowadays, I've renamed typescript...

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Ran Lottem • Dec 20 '22

This looks great!

Does the is method support TS interfaces or just classes that exist during runtime? I ask because I played around with type guards for interfaces using code generation to create runtime representations of interfaces, and I wonder if that's something typia does.

I worked with TS in the past and now I work with Java and protocol buffers, where I also did code generation based on generated Message Java subclasses. Interesting to see what protobuf looks like in TS.

Jeongho Nam • Dec 20 '22

Yes, this is a transformer library generating validation script by analyzing TypeScript type. If you're wondering how typia generates protobuf message, reference test automation code.

I know automatically generated message by current typia is so ugly yet, but it would be reasonable. Also, as you are interested in protobuf, you may understand how typia implemented non-protobuf supported type through detour expression.

github.com/samchon/typia/tree/feat...

Jeongho Nam • Dec 21 '22 • Edited

In another community, someone asked me the reason why such performance gap.

It's my answer and I also paste it here dev.to

"15,000x faster" is just a benchmark program result and such different is not weird considering principle of v8 optimization. It is enough reasonable and descriptable.

typia performs AOT compilation through TypeScript API
ajv and typebox performs JIT compilation through eval() function
class-validator abuses for in statement and dynamic [key, value] allocation in every step

V8 engine optimizes object construction by converting to a hidden class and avoid hash map construction for taking advantages of static class definition. However, if for in statement or dynamic key allocation being used, v8 cannot optimize the object.

The secret of extremely slow validation speed of class-validator is on there. class-validator utilizes the un-optimizable in every process.

for in statement on metadata when iterating raw data to transform
dynamic allocation when transforming to a class instance
dynamic statement on metadata (of decorator)
for in statement when validation

For reference, ajv and typebox are using JIT compilation, generating optimized code in runtime through eval() function (or new Function(string) statement). In v8 engine, priority of optimization is the lowest and it is the principle reaon why typia is faster than such ajv and typebox libraries.

Another reason is how to optimize object accessment. You can see the detailed story about it from below link (this article)