1Scanf.Scanning(3)                OCaml library               Scanf.Scanning(3)
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NAME

6       Scanf.Scanning -  Scanning buffers
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Module

9       Module   Scanf.Scanning
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Documentation

12       Module Scanning
13        : sig end
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17       Scanning buffers
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25       type scanbuf
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28       The  type  of  scanning  buffers.  A scanning buffer is the source from
29       which a formatted input function gets characters. The  scanning  buffer
30       holds  the  current  state of the scan, plus a function to get the next
31       char from the input, and a token buffer to store the string matched  so
32       far.
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34       Note:  a  scan  may  often require to examine one character in advance;
35       when this ``lookahead'' character does not belong to the token read, it
36       is  stored  back  in the scanning buffer and becomes the next character
37       read.
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42       val stdib : scanbuf
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44       The scanning buffer reading from stdin .  stdib is equivalent to  Scan‐
45       ning.from_channel stdin .
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47       Note: when input is read interactively from stdin , the newline charac‐
48       ter that triggers the evaluation is incorporated in  the  input;  thus,
49       scanning specifications must properly skip this character (simply add a
50       '\n' as the last character of the format string).
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55       val from_string : string -> scanbuf
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58       Scanning.from_string s returns a scanning buffer which reads  from  the
59       given  string.   Reading starts from the first character in the string.
60       The end-of-input condition is  set  when  the  end  of  the  string  is
61       reached.
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66       val from_file : string -> scanbuf
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68       Bufferized  file  reading  in text mode. The efficient and usual way to
69       scan text mode files (in effect, from_file returns  a  scanning  buffer
70       that  reads  characters in large chunks, rather than one character at a
71       time as buffers returned by from_channel do).  Scanning.from_file fname
72       returns a scanning buffer which reads from the given file fname in text
73       mode.
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78       val from_file_bin : string -> scanbuf
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80       Bufferized file reading in binary mode.
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85       val from_function : (unit -> char) -> scanbuf
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88       Scanning.from_function f returns a scanning buffer with the given func‐
89       tion as its reading method.
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91       When scanning needs one more character, the given function is called.
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93       When  the  function has no more character to provide, it must signal an
94       end-of-input condition by raising the exception End_of_file .
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99       val from_channel : Pervasives.in_channel -> scanbuf
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102       Scanning.from_channel ic returns a scanning buffer which reads from the
103       input channel ic , starting at the current reading position.
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108       val end_of_input : scanbuf -> bool
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111       Scanning.end_of_input  ib tests the end-of-input condition of the given
112       scanning buffer.
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117       val beginning_of_input : scanbuf -> bool
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120       Scanning.beginning_of_input ib tests the beginning of  input  condition
121       of the given scanning buffer.
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126       val name_of_input : scanbuf -> string
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129       Scanning.file_name_of_input ib returns the name of the character source
130       for the scanning buffer ib .
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137OCamldoc                          2017-03-22                 Scanf.Scanning(3)