Separate Initializer semantic

[RazvanN7]

This PR separates the semantic routines from the AST classes of the Initializer nodes. It is a follow-up to @yebblies 's work #5730

[dlang-bot]

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[RazvanN7]

@UplinkCoder any ideas why compiling druntime leads to CTFE errors?

[UplinkCoder]

@RazvanN7 Nothing that jumps in the eye.
I suggest to leave the code as is, for now.

Are you sure the constructors are getting called correctly ?

[RazvanN7]

@UplinkCoder you mean drop the PR? why?

[UplinkCoder]

The code is not likely to change.
So there is little benefit it splitting it out.

[RazvanN7]

@UplinkCoder

Are you sure the constructors are getting called correctly ?

Yep. I just copy-pasted the code and added i. in front of (1) all the variables that would normally have been parameters and (2) calls to member functions.

So there is little benefit it splitting it out.

I disagree. Refactoring the code this way makes the code easier to read and makes packaging the compiler as a library easier

[wilzbach]

I disagree. Refactoring the code this way makes the code easier to read and makes packaging the compiler as a library easier

I can't agree more. Code is read a lot more than its written and every change that helps to improve the readability of the dmd codebase is imho very useful.
@UplinkCoder don't forgot that there are and will be people who want to understand the dmd codebase in the future.

@RazvanN7 Please don't stop cleaning up and refactoring the frontend. You are doing great and important work!

[RazvanN7]

I plan on doing Expression next.

[ibuclaw]

And C++ headers?

[RazvanN7]

@ibuclaw forgot about those... done.