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

6       Scanf.Scanning - no description
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Module

9       Module   Scanf.Scanning
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Documentation

12       Module Scanning
13        : sig end
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21       type in_channel
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24       The  notion  of input channel for the Scanf module: those channels pro‐
25       vide all the machinery necessary to read from any source of characters,
26       including  a  in_channel  value.   A Scanf.Scanning.in_channel value is
27       also called a formatted input channel or equivalently a  scanning  buf‐
28       fer.   The  type  Scanf.Scanning.scanbuf  below  is  an alias for Scan‐
29       ning.in_channel .  Note  that  a  Scanning.in_channel  is  not  concur‐
30       rency-safe: concurrent use may produce arbitrary values or exceptions.
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33       Since 3.12.0
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36       type scanbuf = in_channel
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39       The  type  of  scanning  buffers.  A scanning buffer is the source from
40       which a formatted input function gets characters. The  scanning  buffer
41       holds  the  current  state of the scan, plus a function to get the next
42       char from the input, and a token buffer to store the string matched  so
43       far.
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45       Note:  a  scanning action may often require to examine one character in
46       advance; when this 'lookahead' character does not belong to  the  token
47       read,  it  is  stored  back in the scanning buffer and becomes the next
48       character yet to be read.
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52       val stdin : in_channel
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54       The standard input notion for the Scanf module.  Scanning.stdin is  the
55       Scanf.Scanning.in_channel formatted input channel attached to stdin .
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57       Note:  in  the  interactive system, when input is read from stdin , the
58       newline character that triggers evaluation is part of the input;  thus,
59       the  scanning specifications must properly skip this additional newline
60       character (for instance, simply add a '\n' as the last character of the
61       format string).
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64       Since 3.12.0
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67       type file_name = string
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70       A convenient alias to designate a file name.
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73       Since 4.00.0
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77       val open_in : file_name -> in_channel
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80       Scanning.open_in  fname  returns  a Scanf.Scanning.in_channel formatted
81       input channel for bufferized reading in text mode from file fname .
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83       Note: open_in returns a formatted input channel that efficiently  reads
84       characters  in  large  chunks;  in contrast, from_channel below returns
85       formatted input channels that must read one character at a time,  lead‐
86       ing to a much slower scanning rate.
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89       Since 3.12.0
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93       val open_in_bin : file_name -> in_channel
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96       Scanning.open_in_bin  fname returns a Scanf.Scanning.in_channel format‐
97       ted input channel for bufferized reading in binary mode from file fname
98       .
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101       Since 3.12.0
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105       val close_in : in_channel -> unit
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107       Closes the in_channel associated with the given Scanf.Scanning.in_chan‐
108       nel formatted input channel.
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111       Since 3.12.0
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115       val from_file : file_name -> in_channel
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117       An alias for Scanf.Scanning.open_in above.
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121       val from_file_bin : string -> in_channel
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123       An alias for Scanf.Scanning.open_in_bin above.
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127       val from_string : string -> in_channel
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130       Scanning.from_string s returns  a  Scanf.Scanning.in_channel  formatted
131       input  channel  which reads from the given string.  Reading starts from
132       the first character in the string.  The end-of-input condition  is  set
133       when the end of the string is reached.
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137       val from_function : (unit -> char) -> in_channel
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140       Scanning.from_function  f returns a Scanf.Scanning.in_channel formatted
141       input channel with the given function as its reading method.
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143       When scanning needs one more character, the given function is called.
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145       When the function has no more character to provide, it must  signal  an
146       end-of-input condition by raising the exception End_of_file .
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150       val from_channel : in_channel -> in_channel
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153       Scanning.from_channel  ic returns a Scanf.Scanning.in_channel formatted
154       input channel which reads from the regular in_channel input channel  ic
155       argument.  Reading starts at current reading position of ic .
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159       val end_of_input : in_channel -> bool
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162       Scanning.end_of_input  ic tests the end-of-input condition of the given
163       Scanf.Scanning.in_channel formatted input channel.
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167       val beginning_of_input : in_channel -> bool
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170       Scanning.beginning_of_input ic tests the beginning of  input  condition
171       of the given Scanf.Scanning.in_channel formatted input channel.
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175       val name_of_input : in_channel -> string
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178       Scanning.name_of_input  ic returns the name of the character source for
179       the given Scanf.Scanning.in_channel formatted input channel.
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182       Since 3.09.0
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188OCamldoc                          2023-07-20                 Scanf.Scanning(3)