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38 lines
1.4 KiB
Markdown
38 lines
1.4 KiB
Markdown
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# Forward
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Was never satisfied with how I did the wrap of the management of the AST.
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For C++, the current design may be as good as it gets for the limitations of the langauge.
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I'll at least try in this issue to brainstorm something simpiler without losing ergonomics.
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This will also be a good place to document the current design.
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## Current Design
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`AST` is the actual managed node object for the library.
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Its raw and really not meant to be used directly.
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All user interaction must be with its pointer so the type they deal with is `AST*`.
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For user-facing code, they should never be giveen a nullptr. Instead, they should be given a designated `Invalid` AST node.
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In order to abstract away constant use of `AST*`, I wanted to provide a wrapper for it.
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The simpliest being just a type alias.
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```cpp
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using Code = AST*;
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```
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This is what the genc library would have to use due to its constraints of a langauge.
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Anything else and it would either be an unergonomic mess of struct wrapping with a mess of macros & procedures to interface with it.
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Further, to provide intuitive filters on the AST, there are AST types (covered in [AST_Types.md](AST_Types.md)).
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These are pure PODS that just have the lay members relevant to the type of AST node they represent.
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Each of them has a Code type alias specific to it.
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Again, the simpliest case for these would be a type alias.
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```cpp
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using struct AST_Typedef CodeTypedef;
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```
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