diff options
| -rw-r--r-- | stdlib/printf.ml | 45 |
1 files changed, 32 insertions, 13 deletions
diff --git a/stdlib/printf.ml b/stdlib/printf.ml index 7e459793b..677ad6323 100644 --- a/stdlib/printf.ml +++ b/stdlib/printf.ml @@ -136,7 +136,7 @@ let extract_format_int conv fmt start stop widths = According to the character [conv], the meta format string is enclosed by the delimitors %{ and %} (when [conv = '{']) or %( and %) (when [conv = '(']). Hence, [sub_format] returns the index of - the character following the ')' or '}' that ends the meta format, + the character following the [')'] or ['}'] that ends the meta format, according to the character [conv]. *) let sub_format incomplete_format bad_conversion_format conv fmt i = let len = Sformat.length fmt in @@ -235,24 +235,40 @@ let summarize_format_type fmt = iter_on_format_args fmt add_conv add_char; Buffer.contents b;; +type num_args = { + mutable num_args : int; + mutable num_skip_args : int; + mutable num_rargs : int; +};; + (* Computes the number of arguments of a format (including flag arguments if any). *) -let nargs_of_format_type fmt = - let num_args = ref 0 - and skip_args = ref 0 in +let num_args_of_format_type fmt = + let nargs = { num_args = 0; num_skip_args = 0; num_rargs = 0; } in + let incr_nargs skip c = + let inc = if c = 'a' then 2 else 1 in + if c = 'r' then nargs.num_rargs <- nargs.num_rargs + 1; + if skip + then nargs.num_skip_args <- nargs.num_skip_args + inc + else nargs.num_args <- nargs.num_args + inc in + let add_conv skip i c = (* Just finishing a meta format: no additional argument to record. *) - if c = ')' || c = '}' then succ i else - let incr_args n = if c = 'a' then n := !n + 2 else n := !n + 1 in - if skip then incr_args skip_args else incr_args num_args; + if c <> ')' && c <> '}' then incr_nargs skip c; succ i and add_char i c = succ i in + iter_on_format_args fmt add_conv add_char; - !skip_args + !num_args;; + nargs;; + +let nargs_of_format_type fmt = + let nargs = num_args_of_format_type fmt in + nargs.num_args + nargs.num_skip_args + nargs.num_rargs;; let list_iter_i f l = let rec loop i = function | [] -> () + | [x] -> f i x (* Tail calling [f] *) | x :: xs -> f i x; loop (succ i) xs in loop 0 l;; @@ -303,10 +319,13 @@ type positional_specification = | Spec_none | Spec_index of index;; (* To scan an optional positional parameter specification, - i.e. an integer followed by a $. - We do not support *$ specifications, since this would lead to type checking - problems: the type would be dependant of the {\em value} of an integer - argument to printf. *) + i.e. an integer followed by a [$]. + We do not support [*$] specifications, since this would lead to type checking + problems: the type of the specified [*$] parameter would be the type of the + corresponding argument to [printf], hence the type of the $n$-th argument to + [printf] with $n$ being the {\em value} of the integer argument defining + [*]; this means type dependency, which is out of scope of the Caml type + algebra. *) let scan_positional_spec fmt got_spec n i = match Sformat.unsafe_get fmt i with | '0'..'9' as d -> @@ -338,7 +357,7 @@ let get_index spec n = | Spec_none -> n | Spec_index p -> p;; -(* Decode a %format and act on it. +(* Decode a format string and act on it. [fmt] is the printf format string, and [pos] points to a [%] character. After consuming the appropriate number of arguments and formatting them, one of the five continuations is called: |