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RFC: add assertion utility to test if a value is "callable"
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RFC:.
Description
Description of the issue (or feature request).
This RFC proposes adding an assertion utility to test whether a value is callable. A value is callable if the value is a function, generator, or an ES6 class.
Prior art:
Package: @stdlib/assert/is-callable
Alias: isCallable
Related Issues
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No.
Questions
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No.
Other
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No.
@kgryte Doesn't isFunction serve the purpose of this package perfectly fine? In what circumstances would the behavior differ?
I believe isCallable is intended to be more generic (see here). For practical purposes in the project, isFunction should suffice for input validation. However, for checking for other function flavors, we may want a looser check to filter out non-callable objects before more specific checks. In general, an object is "callable" if it has a [[call]] slot. This extends beyond normal functions, I believe.