diff options
Diffstat (limited to 'stdlib/scanf.mli')
| -rw-r--r-- | stdlib/scanf.mli | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/stdlib/scanf.mli b/stdlib/scanf.mli index f3049f91eb..65217fc393 100644 --- a/stdlib/scanf.mli +++ b/stdlib/scanf.mli @@ -69,7 +69,7 @@ However, it is also largely different, simpler, and yet more powerful: the formatted input functions are higher-order functionals and the parameter passing mechanism is just the regular function application not - the variable assigment based mechanism which is typical for formatted + the variable assignment based mechanism which is typical for formatted input in imperative languages; the Caml format strings also feature useful additions to easily define complex tokens; as expected within a functional programming language, the formatted input functions also @@ -197,16 +197,19 @@ val bscanf : Scanning.scanbuf -> ('a, 'b, 'c, 'd) scanner;; (** {7 The space character in format strings} *) (** As mentioned above, a plain character in the format string is just - matched with the characters of the input; however, one character is a - special exception to this simple rule: the space character (ASCII code - 32) does not match a single space character, but any amount of + matched with the next character of the input; however, two characters are + special exceptions to this rule: the space character ([' '] or ASCII code + 32) and the line feed character (['\n'] or ASCII code 10). + A space does not match a single space character, but any amount of ``whitespace'' in the input. More precisely, a space inside the format string matches {e any number} of tab, space, line feed and carriage - return characters. + return characters. Similarly, a line feed character in the format string + matches either a single line feed or a carriage return followed by a line + feed. Matching {e any} amount of whitespace, a space in the format string also matches no amount of whitespace at all; hence, the call [bscanf ib - "Price = %d $" (fun p -> p)] succeds and returns [1] when reading an + "Price = %d $" (fun p -> p)] succeeds and returns [1] when reading an input with various whitespace in it, such as [Price = 1 $], [Price = 1 $], or even [Price=1$]. *) @@ -287,6 +290,7 @@ val bscanf : Scanning.scanbuf -> ('a, 'b, 'c, 'd) scanner;; - [N] or [L]: returns the number of tokens read so far. - [!]: matches the end of input condition. - [%]: matches one [%] character in the input. + - [,]: the no-op delimiter for conversion specifications. Following the [%] character that introduces a conversion, there may be the special flag [_]: the conversion that follows occurs as usual, @@ -303,7 +307,7 @@ val bscanf : Scanning.scanbuf -> ('a, 'b, 'c, 'd) scanner;; Notes: - - as mentioned above, a [%s] convertion always succeeds, even if there is + - as mentioned above, a [%s] conversion always succeeds, even if there is nothing to read in the input: it simply returns [""]. - in addition to the relevant digits, ['_'] characters may appear @@ -361,7 +365,7 @@ val bscanf : Scanning.scanbuf -> ('a, 'b, 'c, 'd) scanner;; [End_of_file]: if the end of input is reached the conversion succeeds and simply returns the characters read so far, or [""] if none were read. *) -(** {6 Specialized formatted input functions} *) +(** {6 Specialised formatted input functions} *) val fscanf : in_channel -> ('a, 'b, 'c, 'd) scanner;; (** Same as {!Scanf.bscanf}, but reads from the given channel. @@ -373,7 +377,7 @@ val fscanf : in_channel -> ('a, 'b, 'c, 'd) scanner;; primitives on the channel (reading characters, seeking the reading position, and so on). - As a consequence, never mixt direct low level reading and high level + As a consequence, never mix direct low level reading and high level scanning from the same input channel. *) val sscanf : string -> ('a, 'b, 'c, 'd) scanner;; @@ -397,7 +401,7 @@ val kscanf : val bscanf_format : Scanning.scanbuf -> ('a, 'b, 'c, 'd, 'e, 'f) format6 -> (('a, 'b, 'c, 'd, 'e, 'f) format6 -> 'g) -> 'g;; -(** [bscanf_format ib fmt f] reads a format string token from the scannning +(** [bscanf_format ib fmt f] reads a format string token from the scanning buffer [ib], according to the given format string [fmt], and applies [f] to the resulting format string value. Raise [Scan_failure] if the format string value read does not have the |