Re: [PATCH v2 08/16] apply_ctype: reverse the order of arguments

[Ramsay Jones <ramsay@ramsayjones.plus.com>]

On 26/12/2020 17:51, Luc Van Oostenryck wrote:
> apply_ctype()'s argument order is: src, dst (so the reading
> direction) but the assignment/memcpy() order is much more used:
> 	dst = src;
> 	memcpy(dst, src, n);
> than the order here is confusing.
> 
> So, change its argument order to comply with the memcpy()/
> assignement order and stop the confusion.

Hmm, how about:

"""
apply_ctype()'s argument order is 'src' then 'dst', which reads as
copying 'src' to 'dst'. However, assignment, and many library functions
(eg. memcpy()), use the opposite order for the source and destination
of a copy operation.

So, change the argument order of apply_ctype() to mimic the order of
memcpy()/assignment, to hopefully reduce any potential confusion.
"""

Heh, well that is probably not much better! ;-)

However, what about the (er...) position of the 'pos' argument?
Should it move to the end?

ATB,
Ramsay Jones

> 
> Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
> ---
>  parse.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/parse.c b/parse.c
> index 402214212d77..f106444f75d8 100644
> --- a/parse.c
> +++ b/parse.c
> @@ -1043,7 +1043,7 @@ static struct token *enum_specifier(struct token *token, struct symbol *sym, str
>  	return ret;
>  }
>  
> -static void apply_ctype(struct position pos, struct ctype *src, struct ctype *dst);
> +static void apply_ctype(struct position pos, struct ctype *dst, struct ctype *src);
>  
>  static struct token *typeof_specifier(struct token *token, struct symbol *sym, struct decl_state *ctx)
>  {
> @@ -1056,7 +1056,7 @@ static struct token *typeof_specifier(struct token *token, struct symbol *sym, s
>  		struct symbol *sym;
>  		token = typename(token->next, &sym, NULL);
>  		ctx->ctype.base_type = sym->ctype.base_type;
> -		apply_ctype(token->pos, &sym->ctype, &ctx->ctype);
> +		apply_ctype(token->pos, &ctx->ctype, &sym->ctype);
>  	} else {
>  		struct symbol *typeof_sym = alloc_symbol(token->pos, SYM_TYPEOF);
>  		token = parse_expression(token->next, &typeof_sym->initializer);
> @@ -1427,7 +1427,7 @@ static struct token *generic_qualifier(struct token *next, struct symbol *sym, s
>  	return next;
>  }
>  
> -static void apply_ctype(struct position pos, struct ctype *src, struct ctype *dst)
> +static void apply_ctype(struct position pos, struct ctype *dst, struct ctype *src)
>  {
>  	unsigned long mod = src->modifiers;
>  
> @@ -1529,7 +1529,7 @@ static struct token *declaration_specifiers(struct token *token, struct decl_sta
>  				break;
>  			seen |= Set_S | Set_T;
>  			ctx->ctype.base_type = s->ctype.base_type;
> -			apply_ctype(token->pos, &s->ctype, &ctx->ctype);
> +			apply_ctype(token->pos, &ctx->ctype, &s->ctype);
>  			token = token->next;
>  			continue;
>  		}
>