Add an array from function

[dgud]

To allow array creation from any type of input, for example from binaries without the need to first create a redundant list.

[github-actions]

CT Test Results

    2 files     97 suites   1h 7m 13s ⏱️
2 217 tests 2 165 ✅ 52 💤 0 ❌
2 605 runs  2 549 ✅ 56 💤 0 ❌

Results for commit 5f8b7c2.

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[josevalim]

I wonder if it should be called from_function for consistency with the other from_* functions.

[dgud]

I wonder if it should be called from_function for consistency with the other from_* functions.

Thanks for the suggestion.

Discussed this but we think it is fine as it is, the other from_* discuss the input type and here it can take any user specified data
as input.

Other functions that uses a fun like map and fold doesn't specify that it takes a fun as argument.

[Copilot]

Pull Request Overview

This PR adds new from/2 and from/3 functions to the array module that create arrays by iteratively calling a function with a state until it returns done. This provides a more flexible way to construct arrays compared to from_list/1.

• Adds array:from/2 and array:from/3 functions to build arrays from a generator function
• Includes comprehensive test coverage with from_test_() and real-world examples in import_export/1
• Adds doctest integration via doctests/1 test case

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
lib/stdlib/src/array.erl	Implements the from/2 and from/3 functions with documentation and helper functions
lib/stdlib/test/array_SUITE.erl	Adds test cases for the new functions including unit tests, integration tests, and doctests

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[Copilot]

Corrected spelling of 'IntitialState' to 'InitialState'.

Suggested change

	-spec from(Function, IntitialState :: S) -> array(Type) when
	-spec from(Function, InitialState :: S) -> array(Type) when

[Copilot]

Corrected spelling of 'IntitialState' to 'InitialState'.

Suggested change

	-spec from(Function, IntitialState :: S, Default :: term()) -> array(Type) when
	-spec from(Function, InitialState :: S, Default :: term()) -> array(Type) when

[Copilot]

The import_export/1 test function returns ok instead of an EUnit test tuple. The ?_assert macros at lines 809 and 819 are evaluated for their side effects but the function returns ok, not a test result. Either change the function to return a list of assertions like [?_assert(...), ?_assert(...)], or use regular true = ... assertions without the ?_ prefix.