[Omake] Newbie: removing quotes for command

[Hugo Ferreira]

Hello,

Aleksey Nogin wrote:
> On 21.03.2007 07:00, Hugo Ferreira wrote:
> 
>> I have used:
>>     INCLUDE = $(addprefix -I , $(INCLUDES))
>> and
>>     INCLUDE = $(mapprefix -I , $(INCLUDES))
>>
>> But when the target executes I get:
>>
>> ocamlc "-I " . "-I " ../res_stck "-I " ../qalist "-I " ../term "-I " 
>> ../symbl_tbl "-I " ../compile -dtypes -g -c parser.mli
>>
>> ...which breaks. How do I get rid of the quotes to obtain:
>>
>> ocamlc -I . -I ../res_stck -I ../qalist -I ../term -I ../symbl_tbl -I 
>> ../compile -dtypes -g -c parser.mli
> 
> The issue here is that in OMake the spaces are, in general, significant. 
> Your addprefix call had a space before the "," and that is where the 
> "extra" spaces came from. The quotes is just something that the 
> pretty-printer added to emphasize that the arguments contain spaces, 
> they are not a part of the actual value.
> 

Ok. Easy enough to understand.

> In general, for figuring out things like that, I would recommend using 
> OMake's interactive shell osh that makes it easy to see what's going on.
> 
> E.g. consider the following in osh
> 
> % INCLUDES[] = a b c
> - : <array
>        "a" : Sequence
>        "b" : Sequence
>        "c" : Sequence>
>        : Array
> % addprefix(-I, $(INCLUDES))
> - : <array
>        <sequence "-I" : Sequence "a" : Sequence> : Sequence
>        <sequence "-I" : Sequence "b" : Sequence> : Sequence
>        <sequence "-I" : Sequence "c" : Sequence> : Sequence>
>        : Array
> % addprefix(-I , $(INCLUDES))
> - : <array
>        <sequence "-I " : Sequence "a" : Sequence> : Sequence
>        <sequence "-I " : Sequence "b" : Sequence> : Sequence
>        <sequence "-I " : Sequence "c" : Sequence> : Sequence>
>        : Array
> 
> 

Now I am still baffled. It seems like whether or not I use the space, I 
still get a string (addprefix does not seem to be the in the list you 
provide below).

> BTW, is there some reason why you are implementing your own build 
> recipes for OCaml (note that at the moment you recipes are missing such 
> things as dependency scanning, which may result in all kinds of 
> problems) instead of using the existing build/OCaml.om that comes with 
> OMake?
> 

I cannot use the latest and greatest version OMake which has the 
required recipes for menhir. I am therefore trying to use the files 
provided in its demos (by changing the compilation parameters).

>> I have even attempted to use my own function:
>>
>> F(X, Y) =
>>     T =
>>     foreach (Z, $(X))
>>         T = $(T)$(Y)$(Z)
>>
>> #INCLUDE = $( F $(INCLUDES), -I )
> 
> Same here - you left a space before the ")"!
> 
>> Can anyone also explain how/why/when values are converted to/from a 
>> string?
> 
> This is a really good question. Unfortunately, this is not as systematic 
>  as it probably should be and is not much documented yet.
> 
> In general:
>  - An explicit quotation ($"..." or $'...') would give you a string.
> 
>  - A significant number of built-in functions turn (some of) their 
> arguments into a string or a list of strings (breaking over the unquoted 
> whitespace and array boundaries). For example,
>     - String:
>         case, match (the argument being matched)
>         getenv, setvar, concat, removeprefix (first argument)
>         setenv, get-registry, getvar (all arguments)
>     split (separator argument, when given)
>     - List of strings:
>         string, string-escaped, quote, defined, defined-env, unsetenv 
> (the first and only argument)
>         equal (both arguments)
>         split, concat, removeprefix (last argument)
>         addsuffixes (first argument)
> 
> Usually, the functions only do that "when they need to do a string-like 
> operation on its argument". For example, the split function has to 
> manipulate a string representation of its argument, and the same is true 
> for the removesuffix. On the other hand, addsuffix is not really a 
> string operation (any two values can be concatenated, they do not really 
> have to be strings for that), so it does not stringify its argument. 
> Some functions, however, do stringify their arguments a bit 
> inappropriately - for example, addsuffixes currently does, although it 
> probably should not.
> 
> At the moment, the only way to figure this out for sure (other than 
> manually testing) is to find the code for a built-in function in the 
> src/builtin directory of the source tree - 
> http://svn.metaprl.org/viewvc/mojave/omake-branches/0.9.8.x/src/builtin/ 
> - and look for instances of the string_of_value and strings_of_value 
> calls :-(
> 

So if I want to place the prefix -I to the path, but separated by a 
space so that "ocamlc" may function, how should I go about it.

TIA,
Hugo Ferreira.

> Aleksey
>