Add :single module compile time flag
#15425
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also uses a specific name to not override the `#single_module?` accessor (used to clone a host compiler for macro runs).
This isn't neded, and it's always overriden by the call to `compiler.release!` a few lines below anyway.
The object now has methods to set cross compiler and add emit targets; they're responsible from enabling the single module property. We thus no longer need the two query methods.
| def add_emit_targets(emit_targets) | ||
| @emit_targets |= emit_targets | ||
| @single_module = true unless @emit_targets.none? | ||
| end |
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question: I'm wondering why introduce this specific add method?
The same effect should be achievable with overriding the setter, which keeps the call site identical, and is overall more flexible.
| def add_emit_targets(emit_targets) | |
| @emit_targets |= emit_targets | |
| @single_module = true unless @emit_targets.none? | |
| end | |
| def emit_targets=(@emit_targets) | |
| @single_module = true unless emit_targets.none? | |
| end |
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To be explicit on the action? The same can be said of #cross_compile! I guess (itself influenced by #release! above 🤔
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Oh no this is actually fine. If we wanted an elaborate setter, it would actually need to be able to remove the single module flag for full versatility (@single_module = !emit_targets.none?). But that wouldn't work because @single_module might've been set by a different flag already.
Then the correct implementation would require to keep the individual components independent and only evaluate the full condition in the query method as in the original commit from this PR.
Just like the
:releaseflag it can be useful to know during macros if we're compiling to a single module.For example alongside the
Linkageannotation, we would be able to mark the__crystal_*functions as internal only when compiling to a single module. For example:{% if flag?(:single_module) %} @[Linkage("internal")] {% end %} fun __crystal_once_init : Nil endRelated to #15426