diff options
Diffstat (limited to 'function.c')
| -rw-r--r-- | function.c | 147 |
1 files changed, 50 insertions, 97 deletions
@@ -1719,130 +1719,83 @@ func_if (char* o, char **argv, char *funcname) } #endif -/* This might not be very useful, but the code was simple to - implement, I just had to do it. +/* User-defined functions. Expand the first argument as either a builtin + function or a make variable, in the context of the rest of the arguments + assigned to $1, $2, ... $N. $0 is the name of the function. */ - Here goes anyway - - Apply & User defined functions. - - SYNTAX - - $(apply funcname, arg1, arg2, .. ) - - SEMANTICS - - You can specify a builtin function, for funcname, eg - - f = addprefix - $(apply addprefix,a, b c d) - - This will result in - - ab ac ad - - You can specify your own functions, eg - - funcname=BODY - - BODY contains $(1) .. $(N) as argument markers. - upon expansions the strings ARG1 .. ARGN are substituted for $(1) .. $(N) - into BODY - - Because the funcname is computed as well you can combine this do some - funky things, eg - - map=$(foreach a, $(2), $(apply $(1), $(a))) - - - LIMITATIONS. - - Make has no support for nested lists (or tuples), so you can't do - stuff like (Haskell notation): - - f :: (a,b) -> c -- type of F - map :: (a->b) -> [a] -> b -- type of MAP - - map f [(1,2), (2,3)] -- map F over list containing (1,2) and (2,3) - - to get - - [f (1, 2), f (2, 3)] - - - If only we had nested lists and quotes, we could duplicate LISP in make by - transforming - - $(a, b, c) <-> (a b c) - $(quote $(a, b, c)) <-> '(a b c) - - (or something alike ;-) (We could have automatic integration of - GUILE and make :-) - - [Actually -- why should this be a joke? If we could somehow integrate the - rules and targets into a functional model make could be a lot cleaner in - concept. ] - -*/ char * func_apply (o, argv, funcname) char *o; char **argv; const char *funcname; { - char *userfunc_name; - int func_len; - char *body = 0; - char *expanded_body = 0; + char *fname; + int flen; + char *body; int i; const struct function_table_entry *entry_p; - userfunc_name = argv[0]; - while (isspace (*userfunc_name)) - ++userfunc_name; + /* Applying nothing is a no-op. */ + if (*argv[0] == '\0') + return o; - entry_p = lookup_function (function_table, userfunc_name); + /* There is no way to define a variable with a space in the name, so strip + trailing whitespace as a favor to the user. */ + + flen = strlen (argv[0]); + fname = argv[0] + flen - 1; + while (isspace (*fname)) + --fname; + fname[1] = '\0'; + + flen = fname - argv[0] + 1; + fname = argv[0]; + + /* Are we invoking a builtin function? */ + + entry_p = lookup_function (function_table, fname); - /* builtin function? */ if (entry_p) { - for (i=0; argv[i+1]; i++) + for (i=0; argv[i+1]; ++i) ; - o = expand_builtin_function (o, i, argv + 1, entry_p); - return o; + return expand_builtin_function (o, i, argv + 1, entry_p); } - func_len = strlen (userfunc_name); - body = xmalloc (func_len + 4); - strcpy (body + 2, userfunc_name); - body [func_len+2]=')'; - body [func_len+3]= 0; - body [1]='('; - body [0]='$'; + /* No, so the first argument is the name of a variable to be expanded and + interpreted as a function. Create the variable reference. */ + body = alloca (flen + 4); + body[0]='$'; + body[1]='('; + strcpy (body + 2, fname); + body[flen+2]=')'; + body[flen+3]= '\0'; + + /* Set up arguments $(1) .. $(N). $(0) is the function name. */ push_new_variable_scope (); - /* set up arguments $(1) .. $(N) */ - for (i=0; argv[i]; i++) + for (i=0; *argv; ++i, ++argv) { - char num[10]; - struct variable* var; + char num[11]; + sprintf (num, "%d", i); - var = define_variable (num, strlen (num), argv[i], o_automatic, 0); + define_variable (num, strlen (num), *argv, o_automatic, 0); } - expanded_body = allocated_variable_expand (body); - o = variable_buffer_output (o, expanded_body, strlen (expanded_body)); - free (expanded_body); + /* Expand the body in the context of the arguments, adding the result to + the variable buffer. */ + + o = variable_expand_string (o, body, flen+3); + pop_variable_scope (); - free (body); - return o; + return o + strlen(o); } -#define STRING_SIZE_TUPLE(s) (s), (sizeof(s)-1) +#define STRING_SIZE_TUPLE(_s) (_s), (sizeof(_s)-1) /* Lookup table for builtin functions. @@ -1851,7 +1804,7 @@ func_apply (o, argv, funcname) table. REQUIRED_ARGUMENTS is the minimum number of arguments. A function - can have more, but they will be ignored. + can have more, but if they have less an error will be generated. EXPAND_ALL_ARGUMENTS means that all arguments should be expanded before invocation. Functions that do namespace tricks (foreach) @@ -1881,11 +1834,11 @@ static struct function_table_entry function_table[] = { STRING_SIZE_TUPLE("wordlist"), 3, 1, func_wordlist}, { STRING_SIZE_TUPLE("words"), 1, 1, func_words}, { STRING_SIZE_TUPLE("origin"), 1, 1, func_origin}, + { STRING_SIZE_TUPLE("foreach"), 3, 0, func_foreach}, + { STRING_SIZE_TUPLE("apply"), 1, 1, func_apply}, { STRING_SIZE_TUPLE("error"), 1, 1, func_error}, { STRING_SIZE_TUPLE("warning"), 1, 1, func_error}, - { STRING_SIZE_TUPLE("foreach"), 3, 0, func_foreach}, #ifdef EXPERIMENTAL - { STRING_SIZE_TUPLE("apply"), 1, 1, func_apply}, { STRING_SIZE_TUPLE("eq"), 2, 1, func_eq}, { STRING_SIZE_TUPLE("if"), 3, 0, func_if}, { STRING_SIZE_TUPLE("not"), 1, 1, func_not}, |