mirror of
https://github.com/Ed94/gencpp.git
synced 2024-12-22 07:44:45 -08:00
proofing
This commit is contained in:
parent
cb50f93af5
commit
772d0de5c1
@ -28,7 +28,7 @@ All free from tag identifiers will be prefixed with `gen_` or `GEN_` as the name
|
||||
|
||||
## Generation structure
|
||||
|
||||
1. Files are scaned or parsed
|
||||
1. Files are scanned in or parsed.
|
||||
* If they are parsed, its dude to requiring some changes to either naming, or adding additonal definitions (container generation, typedefs, etc).
|
||||
2. All scanned or parsed code is refactored (identifiers substs) and/or formatted.
|
||||
3. Singleheader generated.
|
||||
@ -53,12 +53,12 @@ A simple `<container>_DefinitionCounter` is used to know how many instantiations
|
||||
|
||||
## Macro Usage
|
||||
|
||||
For the most part macros are kept low usage wise with exception to `_Generic`...
|
||||
For the most part macros are kept minimal with exception to `_Generic`...
|
||||
*(I will be explaining this thing for the rest of this seciton along with gencpp c library's usage of it)*
|
||||
|
||||
The `_Generic` macro plays a key role in reducing direct need of the user to wrangle with mangled definition identifiers of 'templated' containers or for type coercion to map distinct data types to a common code path.
|
||||
|
||||
Because of its lack of use in many C11 libraries and of those that do, they usually end up obfuscating it with excessive preprocessor abuse; Effort was put into minimizing how much of these macros was handled by the preprocessor vs gencpp itself.
|
||||
Because of its lack of use in many C11 libraries.. and, of those that do; they usually end up obfuscating it with excessive preprocessor abuse; Effort was put into minimizing how much of these macros are handled by the preprocessor vs gencpp itself.
|
||||
|
||||
The usual presentation (done bare) is the following:
|
||||
|
||||
@ -72,12 +72,20 @@ _Generic( (arg), \
|
||||
)
|
||||
```
|
||||
|
||||
Where `_Generic` can be considered the follwoing:
|
||||
Where `_Generic` can be considered the follwoing (psuedo-C):
|
||||
|
||||
```c
|
||||
#define type_expr_pair(type, expr) type: expr
|
||||
|
||||
expr _Generic( selector_arg, a_type_expr_pair, ... )
|
||||
C_Expression _Generic( selector_arg, a_type_expr_pair, ... ) {
|
||||
switch( typeof(selector_arg)) {
|
||||
case a_type_expr_pair:
|
||||
return a_type_expr_pari.expr;
|
||||
...
|
||||
default:
|
||||
return default.expr;
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
The first `arg` of _Generic behaves as the "controlling expression" or the expression that resolves to a type which will dictate which of the following expressions provided after to `_Generic` will be resolved as the one used inline for the implemenation.
|
||||
@ -101,15 +109,15 @@ Now, even with gencpp generating this type-expression table, we still need wrapp
|
||||
|
||||
> Discarded expressions still have to be semantically valid.
|
||||
|
||||
The only way to absolve this issue [(without resorting to nasty preprocessor hacks)](https://github.com/JacksonAllan/CC/blob/main/articles/Better_C_Generics_Part_1_The_Extendible_Generic.md) is with wrapping expressions in a 'slot' resolving macros that do not expand if the slot is not defined:
|
||||
The only way to absolve this issue [(without resorting to nasty preprocessor hacks)](https://github.com/JacksonAllan/CC/blob/main/articles/Better_C_Generics_Part_1_The_Extendible_Generic.md) is with wrapping expressions in 'slot' resolving macros that do not expand if the slot is not defined:
|
||||
|
||||
```c
|
||||
GEN_IF_MACRO_DEFINED_INCLUDE_THIS_SLOT( GENERIC_SLOT_1__function_sig )
|
||||
```
|
||||
|
||||
`GENERIC_SLOT_1__function_sig` is our warpper of a "`int, func_use_int`" pair. The `GEN_IF_MACRO_DEFINED_INCLUDE_THIS_SLOT` is a verbse named macro to indicate that that pair will be expanded ONLY IF its defined.
|
||||
`GENERIC_SLOT_1__function_sig` is our warpper of a "`int, func_use_int`" pair. The `GEN_IF_MACRO_DEFINED_INCLUDE_THIS_SLOT` is a verbse named macro to indicate that that pair will be expanded ***ONLY IF*** its defined.
|
||||
|
||||
So for any given templated container interface. Expect the follwoing (taken straight from generation, and just cleaned up formatting...):
|
||||
So for any given templated container interface. Expect the follwoing (taken straight from generation, and just cleaned up formatting):
|
||||
|
||||
```c
|
||||
#define gen_array_append( selector_arg, ... ) _Generic( \
|
||||
|
Loading…
Reference in New Issue
Block a user