update context-independent and remove context-dependent lowering of '

[Sacha0]

This pull request is the next step towards JuliaLang/LinearAlgebra.jl#57 after #24969, #25083, and #25125, completing items 13-17 in #24969's OP's task list. Specifically, this pull request:

1. Rewrites all semantically eager 's in base, test, and stdlib as appropriate.
2. Changes lowering of X' to postfixapostrophize(X), and provides fallback = Adjoint(X).
3. Removes the special lowering for ' in multiplication, left-division, and right-division expressions.

Notes:

1. This pull request is based on remove special lowering for and deprecate .' #25125, from which the first five commits come. Only the last five commits belong to this pull request. I will rebase those commits out once remove special lowering for and deprecate .' #25125 merges. Rebased out.
2. I plan to write a news entry for these changes as part of a large, single news item on the A_mul_B and all that jazz LinearAlgebra.jl#57 (in a later pull request).

Thanks and best!

[Sacha0]

Rebased and fixed the few test failures CI revealed. Assuming CI approves and absent objections or requests for time, I plan to merge these changes this evening PT or later and dive into the last stretch of JuliaLang/LinearAlgebra.jl#57. Best!

[fredrikekre]

Does this really need to be exported?

[Sacha0]

Seems so? Otherwise one must import it broadly?

[TotalVerb]

Why not lower x' to Expr(:call, Symbol("'"), :x)?

[Sacha0]

Why not lower x' to Expr(:call, Symbol("'"), :x)?

Path of least resistance and uncertainty mostly :).

[TotalVerb]

Can also lower to (call (core postfixapostrophe) ,x) like the lowering of a.x to avoid needing to export.

[Sacha0]

Can also lower to (call (core postfixapostrophe) ,x) like the lowering of a.x to avoid needing to export.

Yes, @fredrikekre and I just came to the same conclusion on slack. That's much better. Will fix and push. Thanks! :)

[Sacha0]

x' now lowers to the not-exported Core.postfixapostrophize(x). Thanks!

[StefanKarpinski]

Are we going to have to change the syntax for all of these or are these just temporary?

[Sacha0]

Are we going to have to change the syntax for all of these or are these just temporary?

Sorry, for all of what?

[StefanKarpinski]

A' to adjoint(A), etc.

[Sacha0]

The A' -> adjoint(A) transformations in this pull request guard against the change in lowering causing behavioral changes: The change in lowering impacts neither the behavior of A's appearing in mul, ldiv, and rdiv expressions, nor the behavior of A's generally where A::AbstractVector. But A's appearing in isolation (i.e. not in a mul, ldiv, or rdiv expression) where A::AbstractMatrix are presently eager (adjoint(A)), so the change in lowering does impact their behavior (->Adjoint(A)). Though in most cases Adjoint(A) will serve as well or better going forward, the defensive A' -> adjoint(A) transformations minimize unexpected behavioral changes in the transition. Does that answer your question? :)

[Sacha0]

Thanks all!

[ararslan]

This introduced a new warning during the build:

WARNING: Method definition postfixapostrophize(Any) in module Inference at operators.jl:743 overwritten in module Base at operators.jl:743.

[vtjnash]

Use top not core, and put separate definitions inside each topmodule (Inference and Base) instead of in boot.jl. That'll fix the method overwrite issue.

[Sacha0]

Thanks @vtjnash! Seems Jeff is addressing the warning in #25212 :).