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rel="Chapter" href="Strongly_connected_components.html"> 100<link title="Syntaxerr" rel="Chapter" href="Syntaxerr.html"> 101<link title="Sys" rel="Chapter" href="Sys.html"> 102<link title="Targetint" rel="Chapter" href="Targetint.html"> 103<link title="Tbl" rel="Chapter" href="Tbl.html"> 104<link title="Terminfo" rel="Chapter" href="Terminfo.html"> 105<link title="Thread" rel="Chapter" href="Thread.html"> 106<link title="ThreadUnix" rel="Chapter" href="ThreadUnix.html"> 107<link title="Timings" rel="Chapter" href="Timings.html"> 108<link title="Uchar" rel="Chapter" href="Uchar.html"> 109<link title="Unix" rel="Chapter" href="Unix.html"> 110<link title="UnixLabels" rel="Chapter" href="UnixLabels.html"> 111<link title="Warnings" rel="Chapter" href="Warnings.html"> 112<link title="Weak" rel="Chapter" href="Weak.html"><title>Scanf.Scanning</title> 113</head> 114<body> 115<div class="navbar"> <a class="up" href="Scanf.html" title="Scanf">Up</a> 116 </div> 117<h1>Module <a href="type_Scanf.Scanning.html">Scanf.Scanning</a></h1> 118 119<pre><span class="keyword">module</span> Scanning: <code class="code"><span class="keyword">sig</span></code> <a href="Scanf.Scanning.html">..</a> <code class="code"><span class="keyword">end</span></code></pre><hr width="100%"> 120 121<pre><span id="TYPEin_channel"><span class="keyword">type</span> <code class="type"></code>in_channel</span> </pre> 122<div class="info "> 123The notion of input channel for the <a href="Scanf.html"><code class="code"><span class="constructor">Scanf</span></code></a> module: 124 those channels provide all the machinery necessary to read from any source 125 of characters, including a <a href="Pervasives.html#TYPEin_channel"><code class="code">in_channel</code></a> value. 126 A Scanf.Scanning.in_channel value is also called a <i>formatted input 127 channel</i> or equivalently a <i>scanning buffer</i>. 128 The type <a href="Scanf.Scanning.html#TYPEscanbuf"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.scanbuf</code></a> below is an alias for <code class="code"><span class="constructor">Scanning</span>.in_channel</code>.<br> 129<b>Since</b> 3.12.0<br> 130</div> 131 132 133<pre><span id="TYPEscanbuf"><span class="keyword">type</span> <code class="type"></code>scanbuf</span> = <code class="type"><a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code> </pre> 134<div class="info "> 135The type of scanning buffers. A scanning buffer is the source from which a 136 formatted input function gets characters. The scanning buffer holds the 137 current state of the scan, plus a function to get the next char from the 138 input, and a token buffer to store the string matched so far. 139<p> 140 141 Note: a scanning action may often require to examine one character in 142 advance; when this 'lookahead' character does not belong to the token 143 read, it is stored back in the scanning buffer and becomes the next 144 character yet to be read.<br> 145</div> 146 147 148<pre><span id="VALstdin"><span class="keyword">val</span> stdin</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 149The standard input notion for the <a href="Scanf.html"><code class="code"><span class="constructor">Scanf</span></code></a> module. 150 <code class="code"><span class="constructor">Scanning</span>.stdin</code> is the <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted input channel 151 attached to <a href="Pervasives.html#VALstdin"><code class="code">stdin</code></a>. 152<p> 153 154 Note: in the interactive system, when input is read from 155 <a href="Pervasives.html#VALstdin"><code class="code">stdin</code></a>, the newline character that triggers evaluation is 156 part of the input; thus, the scanning specifications must properly skip 157 this additional newline character (for instance, simply add a <code class="code"><span class="string">'\n'</span></code> as 158 the last character of the format string).<br> 159<b>Since</b> 3.12.0<br> 160</div> 161 162<pre><span id="TYPEfile_name"><span class="keyword">type</span> <code class="type"></code>file_name</span> = <code class="type">string</code> </pre> 163<div class="info "> 164A convenient alias to designate a file name.<br> 165<b>Since</b> 4.00.0<br> 166</div> 167 168 169<pre><span id="VALopen_in"><span class="keyword">val</span> open_in</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEfile_name">file_name</a> -> <a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 170<code class="code"><span class="constructor">Scanning</span>.open_in fname</code> returns a <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted input 171 channel for bufferized reading in text mode from file <code class="code">fname</code>. 172<p> 173 174 Note: 175 <code class="code">open_in</code> returns a formatted input channel that efficiently reads 176 characters in large chunks; in contrast, <code class="code">from_channel</code> below returns 177 formatted input channels that must read one character at a time, leading 178 to a much slower scanning rate.<br> 179<b>Since</b> 3.12.0<br> 180</div> 181 182<pre><span id="VALopen_in_bin"><span class="keyword">val</span> open_in_bin</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEfile_name">file_name</a> -> <a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 183<code class="code"><span class="constructor">Scanning</span>.open_in_bin fname</code> returns a <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted 184 input channel for bufferized reading in binary mode from file <code class="code">fname</code>.<br> 185<b>Since</b> 3.12.0<br> 186</div> 187 188<pre><span id="VALclose_in"><span class="keyword">val</span> close_in</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a> -> unit</code></pre><div class="info "> 189Closes the <a href="Pervasives.html#TYPEin_channel"><code class="code">in_channel</code></a> associated with the given 190 <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted input channel.<br> 191<b>Since</b> 3.12.0<br> 192</div> 193 194<pre><span id="VALfrom_file"><span class="keyword">val</span> from_file</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEfile_name">file_name</a> -> <a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 195An alias for <a href="Scanf.Scanning.html#VALopen_in"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.open_in</code></a> above.<br> 196</div> 197 198<pre><span id="VALfrom_file_bin"><span class="keyword">val</span> from_file_bin</span> : <code class="type">string -> <a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 199An alias for <a href="Scanf.Scanning.html#VALopen_in_bin"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.open_in_bin</code></a> above.<br> 200</div> 201 202<pre><span id="VALfrom_string"><span class="keyword">val</span> from_string</span> : <code class="type">string -> <a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 203<code class="code"><span class="constructor">Scanning</span>.from_string s</code> returns a <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted 204 input channel which reads from the given string. 205 Reading starts from the first character in the string. 206 The end-of-input condition is set when the end of the string is reached.<br> 207</div> 208 209<pre><span id="VALfrom_function"><span class="keyword">val</span> from_function</span> : <code class="type">(unit -> char) -> <a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 210<code class="code"><span class="constructor">Scanning</span>.from_function f</code> returns a <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted 211 input channel with the given function as its reading method. 212<p> 213 214 When scanning needs one more character, the given function is called. 215<p> 216 217 When the function has no more character to provide, it <em>must</em> signal an 218 end-of-input condition by raising the exception <code class="code"><span class="constructor">End_of_file</span></code>.<br> 219</div> 220 221<pre><span id="VALfrom_channel"><span class="keyword">val</span> from_channel</span> : <code class="type"><a href="Pervasives.html#TYPEin_channel">in_channel</a> -> <a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 222<code class="code"><span class="constructor">Scanning</span>.from_channel ic</code> returns a <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted 223 input channel which reads from the regular <a href="Pervasives.html#TYPEin_channel"><code class="code">in_channel</code></a> input 224 channel <code class="code">ic</code> argument. 225 Reading starts at current reading position of <code class="code">ic</code>.<br> 226</div> 227 228<pre><span id="VALend_of_input"><span class="keyword">val</span> end_of_input</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a> -> bool</code></pre><div class="info "> 229<code class="code"><span class="constructor">Scanning</span>.end_of_input ic</code> tests the end-of-input condition of the given 230 <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted input channel.<br> 231</div> 232 233<pre><span id="VALbeginning_of_input"><span class="keyword">val</span> beginning_of_input</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a> -> bool</code></pre><div class="info "> 234<code class="code"><span class="constructor">Scanning</span>.beginning_of_input ic</code> tests the beginning of input condition 235 of the given <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted input channel.<br> 236</div> 237 238<pre><span id="VALname_of_input"><span class="keyword">val</span> name_of_input</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a> -> string</code></pre><div class="info "> 239<code class="code"><span class="constructor">Scanning</span>.name_of_input ic</code> returns the name of the character source 240 for the given <a href="Scanf.Scanning.html#TYPEin_channel"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.in_channel</code></a> formatted input channel.<br> 241<b>Since</b> 3.09.0<br> 242</div> 243 244<pre><span id="VALstdib"><span class="keyword">val</span> stdib</span> : <code class="type"><a href="Scanf.Scanning.html#TYPEin_channel">in_channel</a></code></pre><div class="info "> 245A deprecated alias for <a href="Scanf.Scanning.html#VALstdin"><code class="code"><span class="constructor">Scanf</span>.<span class="constructor">Scanning</span>.stdin</code></a>, the scanning buffer reading from 246 <a href="Pervasives.html#VALstdin"><code class="code">stdin</code></a>.<br> 247</div> 248</body></html>