refH.html (8322B)
1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/1998/REC-html40-19980424/loose.dtd"> 2 <html lang="en"> 3 <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 5 <title>H</title> 6 <link rel="stylesheet" href="doc.css" type="text/css"> 7 </head> 8 <body> 9 10 <h1>H</h1> 11 12 <dl> 13 14 <dt><a name="*Hup"><code>*Hup</code></a> 15 <dd>Global variable holding a (possibly empty) <code>prg</code> body, which will 16 be executed when a SIGHUP signal is sent to the current process. See also 17 <code><a href="refA.html#alarm">alarm</a></code>, <code><a 18 href="refS.html#sigio">sigio</a></code> and <code><a 19 href="refS.html#*Sig1">*Sig[12]</a></code>. 20 21 <pre><code> 22 : (de *Hup (msg 'SIGHUP)) 23 -> *Hup 24 </code></pre> 25 26 <dt><a name="+Hook"><code>+Hook</code></a> 27 <dd>Prefix class for <code><a href="refR.html#+relation">+relation</a></code>s, 28 typically <code><a href="refL.html#+Link">+Link</a></code> or <code><a 29 href="refJ.html#+Joint">+Joint</a></code>. In essence, this maintains an local 30 database in the referred object. See also <a href="ref.html#dbase">Database</a>. 31 32 <pre><code> 33 (rel sup (+Hook +Link) (+Sup)) # Supplier 34 (rel nr (+Key +Number) sup) # Item number, unique per supplier 35 (rel dsc (+Ref +String) sup) # Item description, indexed per supplier 36 </code></pre> 37 38 <dt><a name="+Hook2"><code>+Hook2</code></a> 39 <dd>Prefix class for <code><a href="refI.html#+index">+index</a></code> 40 relations. It maintains both a normal (global) index, and an object-local index 41 in the corresponding <code><a href="refH.html#+Hook">+Hook</a></code> object. 42 See also <a href="ref.html#dbase">Database</a>. 43 44 <pre><code> 45 (rel nm (+Hook2 +IdxFold +String) 3 shop) # Global and shop-local index 46 </code></pre> 47 48 <dt><a name="hash"><code>(hash 'any) -> cnt</code></a> 49 <dd>Generates a 16-bit number (1-65536) from <code>any</code>, suitable as a 50 hash value for various purposes, like randomly balanced <code><a 51 href="refI.html#idx">idx</a></code> structures. See also <code><a 52 href="refC.html#cache">cache</a></code> and <code><a 53 href="refS.html#seed">seed</a></code>. 54 55 <pre><code> 56 : (hash 0) 57 -> 1 58 : (hash 1) 59 -> 55682 60 : (hash "abc") 61 -> 45454 62 </code></pre> 63 64 <dt><a name="hax"><code>(hax 'num) -> sym</code></a> 65 <dt><code>(hax 'sym) -> num</code> 66 <dd>Converts a number <code>num</code> to a string in hexadecimal/alpha 67 notation, or a hexadecimal/alpha formatted string to a number. The digits are 68 represented with '<code>@</code>' (zero) and the letters '<code>A</code>' - 69 '<code>O</code>' (from "alpha" to "omega"). This format is used internally for 70 the names of <code><a href="ref.html#external-io">external symbols</a></code> in 71 the 64-bit version. See also <code><a href="refF.html#fmt64">fmt64</a></code>, 72 <code><a href="refH.html#hex">hex</a></code>, <code><a 73 href="refB.html#bin">bin</a></code> and <code><a 74 href="refO.html#oct">oct</a></code>. 75 76 <pre><code> 77 : (hax 7) 78 -> "G" 79 : (hax 16) 80 -> "A@" 81 : (hax 255) 82 -> "OO" 83 : (hax "A") 84 -> 1 85 </code></pre> 86 87 <dt><a name="hd"><code>(hd 'sym ['cnt]) -> NIL</code></a> 88 <dd>(Debug mode only) Displays a hexadecimal dump of the file given by 89 <code>sym</code>, limited to <code>cnt</code> lines. See also <code><a 90 href="refP.html#proc">proc</a></code>. 91 92 <pre><code> 93 : (hd "lib.l" 4) 94 00000000 23 20 32 33 64 65 63 30 39 61 62 75 0A 23 20 28 # 23dec09abu.# ( 95 00000010 63 29 20 53 6F 66 74 77 61 72 65 20 4C 61 62 2E c) Software Lab. 96 00000020 20 41 6C 65 78 61 6E 64 65 72 20 42 75 72 67 65 Alexander Burge 97 00000030 72 0A 0A 28 64 65 20 74 61 73 6B 20 28 4B 65 79 r..(de task (Key 98 -> NIL 99 </code></pre> 100 101 <dt><a name="head"><code>(head 'cnt|lst 'lst) -> lst</code></a> 102 <dd>Returns a new list made of the first <code>cnt</code> elements of 103 <code>lst</code>. If <code>cnt</code> is negative, it is added to the length of 104 <code>lst</code>. If the first argument is a <code>lst</code>, <code>head</code> 105 is a predicate function returning that argument list if it is <code>equal</code> 106 to the head of the second argument, and <code>NIL</code> otherwise. See also 107 <code><a href="refT.html#tail">tail</a></code>. 108 109 <pre><code> 110 : (head 3 '(a b c d e f)) 111 -> (a b c) 112 : (head 0 '(a b c d e f)) 113 -> NIL 114 : (head 10 '(a b c d e f)) 115 -> (a b c d e f) 116 : (head -2 '(a b c d e f)) 117 -> (a b c d) 118 : (head '(a b c) '(a b c d e f)) 119 -> (a b c) 120 </code></pre> 121 122 <dt><a name="head/3"><code>head/3</code></a> 123 <dd><a href="ref.html#pilog">Pilog</a> predicate that succeeds if the first 124 (string) argument is a prefix of the string representation of the result of 125 applying the <code><a href="refG.html#get">get</a></code> algorithm to the 126 following arguments. Typically used as filter predicate in <code><a 127 href="refS.html#select/3">select/3</a></code> database queries. See also 128 <code><a href="refP.html#pre?">pre?</a></code>, <code><a 129 href="refI.html#isa/2">isa/2</a></code>, <code><a 130 href="refS.html#same/3">same/3</a></code>, <code><a 131 href="refB.html#bool/3">bool/3</a></code>, <code><a 132 href="refR.html#range/3">range/3</a></code>, <code><a 133 href="refF.html#fold/3">fold/3</a></code>, <code><a 134 href="refP.html#part/3">part/3</a></code> and <code><a 135 href="refT.html#tolr/3">tolr/3</a></code>. 136 137 <pre><code> 138 : (? 139 @Nm "Muller" 140 @Tel "37" 141 (select (@CuSu) 142 ((nm +CuSu @Nm) (tel +CuSu @Tel)) 143 (tolr @Nm @CuSu nm) 144 (head @Tel @CuSu tel) ) 145 (val @Name @CuSu nm) 146 (val @Phone @CuSu tel) ) 147 @Nm="Muller" @Tel="37" @CuSu={2-3} @Name="Miller" @Phone="37 4773 82534" 148 -> NIL 149 </code></pre> 150 151 <dt><a name="heap"><code>(heap 'flg) -> cnt</code></a> 152 <dd>Returns the total size of the cell heap space in megabytes. If 153 <code>flg</code> is non-<code>NIL</code>, the size of the currently free space 154 is returned. See also <code><a href="refS.html#stack">stack</a></code> and 155 <code><a href="refG.html#gc">gc</a></code>. 156 157 <pre><code> 158 : (gc 4) 159 -> 4 160 : (heap) 161 -> 5 162 : (heap T) 163 -> 4 164 </code></pre> 165 166 <dt><a name="hear"><code>(hear 'cnt) -> cnt</code></a> 167 <dd>Uses the file descriptor <code>cnt</code> as an asynchronous command input 168 channel. Any executable list received via this channel will be executed in the 169 background. As this mechanism is also used for inter-family communication (see 170 <code><a href="refT.html#tell">tell</a></code>), <code>hear</code> is usually 171 only called explicitly by a top level parent process. 172 173 <pre><code> 174 : (call 'mkfifo "fifo/cmd") 175 -> T 176 : (hear (open "fifo/cmd")) 177 -> 3 178 </code></pre> 179 180 <dt><a name="here"><code>(here ['sym]) -> sym</code></a> 181 <dd>Echoes the current input stream until <code>sym</code> is encountered, or 182 until end of file. See also <code><a href="refE.html#echo">echo</a></code>. 183 184 <pre><code> 185 $ cat hello.l 186 (html 0 "Hello" "lib.css" NIL 187 (<h2> NIL "Hello") 188 (here) ) 189 <p>Hello!</p> 190 <p>This is a test.</p> 191 192 $ pil @lib/http.l @lib/xhtml.l hello.l 193 HTTP/1.0 200 OK 194 Server: PicoLisp 195 Date: Sun, 03 Jun 2007 11:41:27 GMT 196 Cache-Control: max-age=0 197 Cache-Control: no-cache 198 Content-Type: text/html; charset=utf-8 199 200 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 201 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> 202 <head> 203 <title>Hello</title> 204 <link rel="stylesheet" href="http://:/lib.css" type="text/css"/> 205 </head> 206 <body><h2>Hello</h2> 207 <p>Hello!</p> 208 <p>This is a test.</p> 209 </body> 210 </html> 211 </code></pre> 212 213 <dt><a name="hex"><code>(hex 'num ['num]) -> sym</code></a> 214 <dt><code>(hex 'sym) -> num</code> 215 <dd>Converts a number <code>num</code> to a hexadecimal string, or a hexadecimal 216 string <code>sym</code> to a number. In the first case, if the second argument 217 is given, the result is separated by spaces into groups of such many digits. See 218 also <code><a href="refB.html#bin">bin</a></code>, <code><a 219 href="refO.html#oct">oct</a></code>, <code><a 220 href="refF.html#fmt64">fmt64</a></code>, <code><a 221 href="refH.html#hax">hax</a></code> and <code><a 222 href="refF.html#format">format</a></code>. 223 224 <pre><code> 225 : (hex 273) 226 -> "111" 227 : (hex "111") 228 -> 273 229 : (hex 1234567 4) 230 -> "12 D687" 231 </code></pre> 232 233 <dt><a name="host"><code>(host 'any) -> sym</code></a> 234 <dd>Returns the hostname corresponding to the given IP address. See also 235 <code><a href="refA.html#*Adr">*Adr</a></code>. 236 237 <pre><code> 238 : (host "80.190.158.9") 239 -> "www.leo.org" 240 </code></pre> 241 242 </dl> 243 244 </body> 245 </html>