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</span><a href="chap27.html#X7A79DEE07A41B8EF"> <span class="ContSS"><br /><span class="nocss"> </span><a href="chap27.html#X87D03FC0809DB6EC"> <span class="ContSS"><br /><span class="nocss"> </span><a href="chap27.html#X7C74C33784CDED6C"> <span class="ContSS"><br /><span class="nocss"> </span><a href="chap27.html#X84A6A2637FB35A32"> <span class="ContSS"><br /><span class="nocss"> </span><a href="chap27.html#X879461D77C81100B"> <span class="ContSS"><br /><span class="nocss"> </span><a href="chap27.html#X802469C47F886A59"> <span class="ContSS"><br /><span class="nocss"> </span><a href="chap27.html#X870A71D47B0E936E"> <span class="ContSS"><br /><span class="nocss"> </span><a href="chap27.html#X78AF8EA887532B5B"> </div></div> <div class="ContSect"><span class="tocline"><span class="nocss"> </span><a href="chap27.html#X </span> </div> </div> <h3>27 <span class="Heading">Strings and Characters</span></h3> <p><a id="X7A90690B78260194" name="X7A90690B78260194"></a></p> <h4>27.1 <span class="Heading">IsChar and IsString</span></h4> <p><a id="X80CFAE128560E064" name="X80CFAE128560E064"></a></p> <h5>27.1-1 IsChar</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p>A <em>character</em> is simply an object in <strong class="pkg">GAP</strong> that represents an arb <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">x:= 'a'; IsChar( x );</span> 'a' true <span class="GAPprompt">gap></span> <span class="GAPinput">'*';</span> '*' </pre></div> <p><a id="X78723B5D795A3B6D" name="X78723B5D795A3B6D"></a></p> <h5>27.1-2 IsString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p>A <em>string</em> is a dense list (see <code class="func">IsList</code> (<a href="chap21.html#X7C4 <p>A string literal can either be entered as the list of characters or by writing the characters be I (27.4-1) below for more detail<p>Each character, in particular those which cannot be typed directly from the keyboard, can als <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">s1 := ['H','e','l','l','o',' ','w "Hello world." <span class="GAPprompt">gap></span> <span class="GAPinput">IsString( s1 );</span> true <span class="GAPprompt">gap></span> <span class="GAPinput">s2 := "Hello world.";</span> "Hello world." <span class="GAPprompt">gap></span> <span class="GAPinput">s1 = s2;</span> true <span class="GAPprompt">gap></span> <span class="GAPinput">s3 := ""; # the empty string</span> "" <span class="GAPprompt">gap></span> <span class="GAPinput">s3 = [];</span> true <span class="GAPprompt">gap></span> <span class="GAPinput">IsString( [] );</span> true <span class="GAPprompt">gap></span> <span class="GAPinput">IsString( "123" ); IsString( 123 );</ true false <span class="GAPprompt">gap></span> <span class="GAPinput">IsString( [ '1', '2', '3' ] );</span> true <span class="GAPprompt">gap></span> <span class="GAPinput">IsString( [ '1', '2', , '4' ] ); # strin false <span class="GAPprompt">gap></span> <span class="GAPinput">IsString( [ '1', '2', 3 ] ); # strings m false </pre></div> <p><a id="X7B1B45C587A72F96" name="X7B1B45C587A72F96"></a></p> <h5>27.1-3 <span class="Heading">Strings As Lists</span></h5> <p>Note that a string is just a special case of a list. So everything that is possible for lists (see < <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">Length( s2 );</span> 12 <span class="GAPprompt">gap></span> <span class="GAPinput">s2[2];</span> 'e' <span class="GAPprompt">gap></span> <span class="GAPinput">'a' in s2;</span> false <span class="GAPprompt">gap></span> <span class="GAPinput">s2[2] := 'a';; s2;</span> "Hallo world." <span class="GAPprompt">gap></span> <span class="GAPinput">s1{ [1..4] };</span> "Hell" <span class="GAPprompt">gap></span> <span class="GAPinput">Concatenation( s1{ [ 1 .. 6 ] }, s1{ [ 1 . "Hello Hell" </pre></div> <p><a id="X7EA6CA7486D7E9DD" name="X7EA6CA7486D7E9DD"></a></p> <h5>27.1-4 <span class="Heading">Printing Strings</span></h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Vi <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Pr <p>If a string is displayed by <code class="func">View</code> (<a href="chap6.html#X851902C583B8 <p>Strings behave differently from other <strong class="pkg">GAP</strong> objects with respect t <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">s4:= "abc\"def\nghi";; <span class="GAPprompt">gap></span> <span class="GAPinput">View( s4 ); Print( "\n" );</span> "abc\"def\nghi" <span class="GAPprompt">gap></span> <span class="GAPinput">ViewObj( s4 ); Print( "\n" );</span> "abc\"def\nghi" <span class="GAPprompt">gap></span> <span class="GAPinput">PrintObj( s4 ); Print( "\n" );</span> "abc\"def\nghi" <span class="GAPprompt">gap></span> <span class="GAPinput">Print( s4 ); Print( "\n" );</span> abc"def ghi <span class="GAPprompt">gap></span> <span class="GAPinput">s := "German uses strange charact "German uses strange characters: äöüß\n" <span class="GAPprompt">gap></span> <span class="GAPinput">Print(s);</span> German uses strange characters: äöüß <span class="GAPprompt">gap></span> <span class="GAPinput">PrintObj(s); Print( "\n" );</span> "German uses strange characters: \303\244\303\266\303\274\303\237\n" </pre></div> <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">s := "\007";</span> "\007" <span class="GAPprompt">gap></span> <span class="GAPinput">Print(s); # rings bell in many termin </pre></div> <p>Note that only those line breaks are printed by <code class="func">Print</code> (<a href="chap6. <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">s1;</span> "Hello world." <span class="GAPprompt">gap></span> <span class="GAPinput">Print( s1 );</span> Hello world.gap> Print( s1, "\n" ); Hello world. <span class="GAPprompt">gap></span> <span class="GAPinput">Print( s1, "\nnext line\n" );</span> Hello world. next line </pre></div> <p><a id="X82E5F5AB818F32DB" name="X82E5F5AB818F32DB"></a></p> <h4>27.2 <span class="Heading">Special Characters</span></h4> <p>There are a number of <em>special character sequences</em> that can be used between the singlequo <dl> <dt><strong class="Mark"> <code class="code">\n</code></strong></dt> <dd><p><em>newline character</em>. This is the character that, at least on UNIX systems, separates li </dd> <dt><strong class="Mark"> <code class="code">\" <dd><p><em>doublequote character</em>. Inside a string a doublequote must be escaped by the backslas </dd> <dt><strong class="Mark"> <code class="code">\' <dd><p><em>singlequote character</em>. Inside a character a singlequote must escaped by the backsla </dd> <dt><strong class="Mark"> <code class="code">\\</code></strong></dt> <dd><p><em>backslash character</em>. Inside a string a backslash must be escaped by another backslas </dd> <dt><strong class="Mark"> <code class="code">\b</code></strong></dt> <dd><p><em>backspace character</em>. Printing this character should have the effect of moving the cu </dd> <dt><strong class="Mark"> <code class="code">\r</code></strong></dt> <dd><p><em>carriage return character</em>. Printing this character should have the effect of moving </dd> <dt><strong class="Mark"> <code class="code">\c</code></strong></dt> <dd><p><em>flush character</em>. This character is not printed. Its purpose is to flush the output que </dd> <dt><strong class="Mark"> <code class="code">\XYZ</code></strong></dt> <dd><p>with <code class="code">X</code>, <code class="code">Y</code>, <code class="code">Z</code> three </dd> <dt><strong class="Mark"> <code class="code">\0xYZ</code></strong></dt> <dd><p>with <code class="code">Y</code>, and <code class="code">Z</code> hexadecimal digits, that is o </dd> <dt><strong class="Mark"> other</strong></dt> <dd><p>For any other character the backslash is ignored.</p> </dd> </dl> <p>Again, if the line is displayed as result of an evaluation, those escape sequences are display <p>Only <code class="func">Print</code> (<a href="chap6.html#X7AFA64D97A1F39A3"><span class="R <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">"This is one line.\nThis is ano "This is one line.\nThis is another line.\n" <span class="GAPprompt">gap></span> <span class="GAPinput">Print( last );</span> This is one line. This is another line. </pre></div> <p>Note in particular that it is not allowed to enclose a <var class="Arg">newline</var> inside the s <p><a id="X7E70384E7D0B7083" name="X7E70384E7D0B7083"></a></p> <h4>27.3 <span class="Heading">Triple Quoted Strings</span></h4> <p>Another method of entering strings in GAP is triple quoted strings. Triple quoted strings ign <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">"""Print("\n")""";</span> "Print(\"\\n\")" </pre></div> <p>Triple quoted strings are represented internally identically to all other strings, they onl gap> , > or brk> will have this beginning part removed.<p><a id="X82AEC07487C45ECD" name="X82AEC07487C45ECD"></a></p> <h4>27.4 <span class="Heading">Internally Represented Strings</span></h4> <p><a id="X7A17EDF8785C9F58" name="X7A17EDF8785C9F58"></a></p> <h5>27.4-1 IsStringRep</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p><code class="func">IsStringRep</code> is a special (internal) representation of dense lists o <p><a id="X7CE2415F7FEC5809" name="X7CE2415F7FEC5809"></a></p> <h5>27.4-2 ConvertToStringRep</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Co <p>If <var class="Arg">obj</var> is a dense internally represented list of characters then <code cla <p><a id="X7FFC464683CC8023" name="X7FFC464683CC8023"></a></p> <h5>27.4-3 CopyToStringRep</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Co <p>If <var class="Arg">obj</var> is a dense internally represented list of characters then <code cla <p><a id="X7D944D507CBB24CD" name="X7D944D507CBB24CD"></a></p> <h5>27.4-4 IsEmptyString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p><code class="func">IsEmptyString</code> returns <code class="keyw">true</code> if <var class="A <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">l:= [];; IsString( l ); IsEmptyStrin true false true <span class="GAPprompt">gap></span> <span class="GAPinput">l; ConvertToStringRep( l ); l;</span> [ ] "" <span class="GAPprompt">gap></span> <span class="GAPinput">IsEmptyString( l ); IsEmptyString( true true false <span class="GAPprompt">gap></span> <span class="GAPinput">ll:= [ 'a', 'b' ]; IsStringRep( ll ); C "ab" false <span class="GAPprompt">gap></span> <span class="GAPinput">ll; IsStringRep( ll );</span> "ab" true </pre></div> <p><a id="X836078DC829A8221" name="X836078DC829A8221"></a></p> <h5>27.4-5 EmptyString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Em <p>Returns: a string</p> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Sh <p>Returns: nothing</p> <p>The function <code class="func">EmptyString</code> returns an empty string in internal repres <p>The function <code class="func">ShrinkAllocationString</code> gives back to <strong class="p <p>These functions are intended for saving some of <strong class="pkg">GAP</strong>s memory in cer <p><a id="X7DA671FC7F490C16" name="X7DA671FC7F490C16"></a></p> <h5>27.4-6 CharsFamily</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Ch <p>Each character lies in the family <code class="func">CharsFamily</code>, each nonempty string <p><a id="X82F980A17FE84AA4" name="X82F980A17FE84AA4"></a></p> <h4>27.5 <span class="Heading">Recognizing Characters</span></h4> <p><a id="X78566FD57B95ECBE" name="X78566FD57B95ECBE"></a></p> <h5>27.5-1 IsDigitChar</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p>checks whether the character <var class="Arg">c</var> is a digit, i.e., occurs in the string <code <p><a id="X854114A97BAFEAEA" name="X854114A97BAFEAEA"></a></p> <h5>27.5-2 IsLowerAlphaChar</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p>checks whether the character <var class="Arg">c</var> is a lowercase alphabet letter, i.e., occ <p><a id="X87B1A13D81353AD8" name="X87B1A13D81353AD8"></a></p> <h5>27.5-3 IsUpperAlphaChar</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p>checks whether the character <var class="Arg">c</var> is an uppercase alphabet letter, i.e., oc <p><a id="X84634DF67A431D26" name="X84634DF67A431D26"></a></p> <h5>27.5-4 IsAlphaChar</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Is <p>checks whether the character <var class="Arg">c</var> is either a lowercase or an uppercase alph <p><a id="X8127954B79B8A0DA" name="X8127954B79B8A0DA"></a></p> <h4>27.6 <span class="Heading">Comparisons of Strings</span></h4> <p><a id="X79538F138286739A" name="X79538F138286739A"></a></p> <h5><code>27.6-1 \=</code></h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ \=< <p>The equality operator <code class="code">=</code> returns <code class="keyw">true</code> if the t <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">"Hello world.\n" = "Hello world.\ true <span class="GAPprompt">gap></span> <span class="GAPinput">"Hello World.\n" = "Hello world.\ false <span class="GAPprompt">gap></span> <span class="GAPinput">"Hello world." = "Hello world.\n" false <span class="GAPprompt">gap></span> <span class="GAPinput">"Goodbye world.\n" = "Hello world false <span class="GAPprompt">gap></span> <span class="GAPinput">[ 'a', 'b' ] = "ab";</span> true </pre></div> <p><a id="X8129E3A785F60093" name="X8129E3A785F60093"></a></p> <h5><code>27.6-2 \<</code></h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ \<</ <p>The ordering of strings is lexicographically according to the order implied by the underlyin <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">"Hello world.\n" < "Hello world.\n false <span class="GAPprompt">gap></span> <span class="GAPinput"># in ASCII capitals range before smal <span class="GAPprompt">gap></span> <span class="GAPinput">"Hello World." < "Hello world.";</s true <span class="GAPprompt">gap></span> <span class="GAPinput">"Hello world." < "Hello world.\n"; true <span class="GAPprompt">gap></span> <span class="GAPinput"># G comes before H, in ASCII at least:</ <span class="GAPprompt">gap></span> <span class="GAPinput">"Goodbye world.\n" < "Hello world. true </pre></div> <p>Strings can be compared via <code class="code"><</code> with certain <strong class="pkg">GAP</str <p><a id="X7E72717A82A309F5" name="X7E72717A82A309F5"></a></p> <h4>27.7 <span class="Heading">Operations to Produce or Manipulate Strings</span></h4> <p>For the possibility to print <strong class="pkg">GAP</strong> objects to strings, see <a href="c <p><a id="X792FB3A1849FD739" name="X792FB3A1849FD739"></a></p> <h5>27.7-1 DisplayString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Di <p>Returns a string which could be used to display the object <var class="Arg">obj</var> in a nice, fo <p><a id="X8482132779EA7A23" name="X8482132779EA7A23"></a></p> <h5>27.7-2 DEFAULTDISPLAYSTRING</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ DE <p>This is the default value for <code class="func">DisplayString</code> (<a href="chap27.html#X <p><a id="X7803FBCA79DB5529" name="X7803FBCA79DB5529"></a></p> <h5>27.7-3 ViewString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Vi <p><code class="func">ViewString</code> returns a string which would be displayed by <code class=" <p><a id="X7BBDF9D383595425" name="X7BBDF9D383595425"></a></p> <h5>27.7-4 DEFAULTVIEWSTRING</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ DE <p>This is the default value for <code class="func">ViewString</code> (<a href="chap27.html#X780 <p><a id="X7B3CC87285DEC23D" name="X7B3CC87285DEC23D"></a></p> <h5>27.7-5 PrintString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Pr <p><code class="func">PrintString</code> returns a representation of <var class="Arg">obj</var>, w <p>If <var class="Arg">length</var> is given it must be an integer. The absolute value gives the mini <p>In the two argument case, the string returned is a new mutable string (in particular not a part o <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">PrintString(123);PrintString([1 "123" "[ 1, 2, 3 ]" </pre></div> <p><code class="func">PrintString</code> is entitled to put in additional control characters <cod <p><a id="X81FB5BE27903EC32" name="X81FB5BE27903EC32"></a></p> <h5>27.7-6 String</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ St <p><code class="func">String</code> returns a representation of <var class="Arg">obj</var>, which m <p>If <var class="Arg">length</var> is given it must be an integer. The absolute value gives the mini <p>In the two argument case, the string returned is a new mutable string (in particular not a part o <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">String(123);String([1,2,3]);</sp "123" "[ 1, 2, 3 ]" </pre></div> <p><code class="func">String</code> must not put in additional control characters <code class="co <p><a id="X86AACCE987F74FA5" name="X86AACCE987F74FA5"></a></p> <h5>27.7-7 StripLineBreakCharacters</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ St <p>This function takes a string <var class="Arg">st</var> as an argument and removes all control cha <p><a id="X865FBB7E788017DD" name="X865FBB7E788017DD"></a></p> <h5>27.7-8 HexStringInt</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ He <p>returns a string which represents the integer <var class="Arg">int</var> with hexadecimal digi <p><a id="X7BB1059185AB4F84" name="X7BB1059185AB4F84"></a></p> <h5>27.7-9 StringPP</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ St <p>returns a string representing the prime factor decomposition of the integer <var class="Arg"> <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">StringPP(40320);</span> "2^7*3^2*5*7" </pre></div> <p><a id="X79C8280A853D8FA9" name="X79C8280A853D8FA9"></a></p> <h5>27.7-10 WordAlp</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Wo <p>returns a string that is the <var class="Arg">nr</var>-th word over the alphabet list <var class=" <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">List([0..5],i->WordAlp("abc",i)) [ "", "a", "b", "c", "aa", "ab" ] </pre></div> <p><a id="X798A0F35852ABDAD" name="X798A0F35852ABDAD"></a></p> <h5>27.7-11 LowercaseString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Lo <p>Returns a lowercase version of the string <var class="Arg">string</var>, that is, a string in whi <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">LowercaseString("This Is UpperC "this is uppercase" </pre></div> <p><a id="X87A2F2557DE7EE08" name="X87A2F2557DE7EE08"></a></p> <h5>27.7-12 LowercaseChar</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Lo <p>Returns the lowercase version of the character <var class="Arg">character</var>.</p> <p><a id="X7E7E5F5B7FED56A0" name="X7E7E5F5B7FED56A0"></a></p> <h5>27.7-13 UppercaseString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Up <p>Returns a uppercase version of the string <var class="Arg">string</var>, that is, a string in whi <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">UppercaseString("This Is UpperC "THIS IS UPPERCASE" </pre></div> <p><a id="X81E0AEE687200505" name="X81E0AEE687200505"></a></p> <h5>27.7-14 UppercaseChar</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Up <p>Returns the uppercase version of the character <var class="Arg">character</var>.</p> <p><a id="X86E897D486DCFEAB" name="X86E897D486DCFEAB"></a></p> <h5>27.7-15 SplitString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Sp <p>This function accepts a string <var class="Arg">string</var> and lists <var class="Arg">seps</va <p>Both arguments <var class="Arg">seps</var> and <var class="Arg">wspace</var> can be single charac <p>Each string in the resulting list of substring does not contain any characters in <var class="A <p>A character that occurs both in <var class="Arg">seps</var> and <var class="Arg">wspace</var> is tr <p>A separator at the end of a string is interpreted as a terminator; in this case, the separator do <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">SplitString( "substr1:substr2::s [ "substr1", "substr2", "", "substr4" ] <span class="GAPprompt">gap></span> <span class="GAPinput">SplitString( "a;b;c;d;", ";" );</sp [ "a", "b", "c", "d" ] <span class="GAPprompt">gap></span> <span class="GAPinput">SplitString( "/home//user//dir/" [ "home", "user", "dir" ] </pre></div> <p><a id="X864F0A9078D4DE0E" name="X864F0A9078D4DE0E"></a></p> <h5>27.7-16 ReplacedString</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Re <p>replaces occurrences of the string <var class="Arg">old</var> in <var class="Arg">string</var> by < <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">ReplacedString("abacab","a","zl "zlbzlczlb" <span class="GAPprompt">gap></span> <span class="GAPinput">ReplacedString("ababa", "aba","c "cba" <span class="GAPprompt">gap></span> <span class="GAPinput">ReplacedString("abacab","a","ba "babbacbab" </pre></div> <p><a id="X806379367A53D171" name="X806379367A53D171"></a></p> <h5>27.7-17 NormalizeWhitespace</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ No <p>This function changes the string <var class="Arg">string</var> in place. The characters <code cl <p>See <code class="func">NormalizedWhitespace</code> (<a href="chap27.html#X8685DE9386E577 <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">s := " x y \n\n\t\r z\n \n";< " x y \n\n\t\r z\n \n" <span class="GAPprompt">gap></span> <span class="GAPinput">NormalizeWhitespace(s);</span> <span class="GAPprompt">gap></span> <span class="GAPinput">s;</span> "x y z" </pre></div> <p><a id="X8685DE9386E57771" name="X8685DE9386E57771"></a></p> <h5>27.7-18 NormalizedWhitespace</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ No <p>This function returns a copy of string <var class="Arg">str</var> to which <code class="func">Nor <p><a id="X86EBB6EB829723E4" name="X86EBB6EB829723E4"></a></p> <h5>27.7-19 RemoveCharacters</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Re <p>Both arguments must be strings. This function efficiently removes all characters given in <va <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">s := "ab c\ndef\n\ng h i .\n";< "ab c\ndef\n\ng h i .\n" <span class="GAPprompt">gap></span> <span class="GAPinput">RemoveCharacters(s, " \n\t\r"); # <span class="GAPprompt">gap></span> <span class="GAPinput">s;</span> "abcdefghi." </pre></div> <p><a id="X84624FEB825EC4B5" name="X84624FEB825EC4B5"></a></p> <h5>27.7-20 JoinStringsWithSeparator</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Jo <p>joins <var class="Arg">list</var> (a list of strings) after interpolating <var class="Arg">sep</ <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">list := List([1..10], String);</spa [ "1", "2", "3", "4", "5", "6", "7", "8", "9", "10" ] <span class="GAPprompt">gap></span> <span class="GAPinput">JoinStringsWithSeparator(list);< "1,2,3,4,5,6,7,8,9,10" <span class="GAPprompt">gap></span> <span class="GAPinput">JoinStringsWithSeparator(["The" "The quick brown fox" <span class="GAPprompt">gap></span> <span class="GAPinput">new:= JoinStringsWithSeparator([ "a,\n b,\n c,\n d" <span class="GAPprompt">gap></span> <span class="GAPinput">Print(" ", new, "\n");</span> a, b, c, d </pre></div> <p><a id="X79F8FFC5876D854A" name="X79F8FFC5876D854A"></a></p> <h5>27.7-21 Chomp</h5> <div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ Ch <p>Like the similarly named Perl function, <code class="func">Chomp</code> removes a trailing new <div class="example"><pre> <span class="GAPprompt">gap></span> <span class="GAPinput">Chomp("The quick brown fox jump "The quick brown fox jumps over the lazy dog." <span class="GAPprompt">gap></span> <span class="GAPinput">Chomp("The quick brown fox jump "The quick brown fox jumps over the lazy dog." --> -------------------- --> maximum size reached --> -------------------- [ Verzeichnis aufwärts0.16unsichere Verbindung Übersetzung europäischer Sprachen durch Browser ] |
2026-03-28