Bug 20440 – Associative arrays with values whose opAssign doesn't return a ref don't support require function

import std.bigint; void main(){ BigInt[int] foo; foo.require(0, BigInt.init); } Does not compile: /usr/include/dmd/druntime/import/object.d(2600): Error: (*p).opAssign(value()) is not an lvalue and cannot be modified test.d(4): Error: template instance object.require!(int, BigInt) error instantiating

with v2.086.1, either of the following permits the test case to compile: in phobos/std/bigint.d, add a 'ref' to the following return type: /// Assignment from another BigInt. BigInt opAssign(T:BigInt)(T x) pure @nogc in druntime/import/object.d, change the last line of require from return found ? *p : (*p = value); to if (!found) *p = value; return *p;

@GoaLitiuM created dlang/phobos pull request #7312 "Fix Issue 20440 - Associative arrays of BigInt does not support require or get function" fixing this issue: - Fix Issue 20440 - Associative arrays of BigInt does not support require or get function https://github.com/dlang/phobos/pull/7312

The fix in PR 7312 only fixes this for BigInt specifically. If we are not going to require that opAssign return ref for every type, this should be fixed in druntime instead. In other words: this is a bug in require(), not in BigInt.

@n8sh created dlang/druntime pull request #2869 "Fix Issue 20440 - Associative arrays of BigInt does not support require or get function" fixing this issue: - Fix Issue 20440 - Associative arrays of BigInt does not support require or get function Applies to any type with a custom opAssign that doesn't return a ref to self https://github.com/dlang/druntime/pull/2869

Adjusting title to be more general. Also it seems that `get` currently works with BigInt.

dlang/druntime pull request #2869 "Fix Issue 20440 - Associative arrays with values whose opAssign doesn't return a ref don't support require function" was merged into master: - 35538a12511a1e98816dd846003cd9259d92f931 by Nathan Sashihara: Fix Issue 20440 - Associative arrays with values whose opAssign doesn't return a ref don't support require function https://github.com/dlang/druntime/pull/2869