Bug 15752 – Diagnostic: Better Error Message for Assigning Incorrect AA Empty Value

Because of the use of [] to enclose AA assignment, one could be forgiven in accidentally doing something like this: void main() { int[int] a = []; } Which results in the very unhelpful message: Error: can't have associative array key of void Of course, the right answer is to use null, but again, the similarities with array literals one could be expected to make this mistake. The error message is also different when trying to do this for an optional function parameter. void func(int[int] b = []) { } void main() { func(); } Error: cannot implicitly convert expression ([]) of type void[] to int[int] The message should be something like this: Error: can't have associative array key of void. Perhaps you meant to initialize an empty AA with null?

@ntrel created dlang/dmd pull request #15599 "Fix Issue 15752 - Better Error Message for Assigning Incorrect AA Emp…" fixing this issue: - Fix Issue 15752 - Better Error Message for Assigning Incorrect AA Empty Value Also show location of value with missing index in initializer. https://github.com/dlang/dmd/pull/15599

dlang/dmd pull request #15599 "Fix Issue 15752 - Better Error Message for Assigning Incorrect AA Emp…" was merged into master: - 776919e2a76bf7619cb628cd052cca3443028b40 by Nick Treleaven: Fix Issue 15752 - Better Error Message for Assigning Incorrect AA Empty Value Also show location of value with missing index in initializer. https://github.com/dlang/dmd/pull/15599