# Method-style builtins

> If obj.method(args) is called and obj is an identifier, the interpreter first checks for a registered builtin named "obj.method" . If found, it is called with just args (not...

Website: https://harnlang.com/spec/language/22-method-style-builtins.html

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## Method-style builtins

If `obj.method(args)` is called and `obj` is an identifier, the interpreter first checks
for a registered builtin named `"obj.method"`. If found, it is called with just `args`
(not `obj`). This enables namespaced builtins like `experience_bank.save(...)`
and `negative_knowledge.record(...)`.

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## Read next

- [Iterator protocol](https://harnlang.com/spec/language/21-iterator-protocol.md)
- [Runtime errors](https://harnlang.com/spec/language/23-runtime-errors.md)