内容讲义成果

Vine’sPerl

Simplestatement+

Vine’sPerlPerl入门和提 Lesson

Simple_statmodifier!!AlwaysevaluatesConditionbeforeexecutedoBLOCKwhilecond;runBLOCKoncebeforeevaluateprint"\$Aisnegitive!"if$A<0;die"SOS!"if($fail);$B=1/$Aunless$A==($sum,$j)=(0,1);do{$sum+=$j}while++$j<=$sum=0;$sum+=$_foreach(1..100);#loopson$hash{$key}=$vunlessdefned($hash{$key});#avoidover-$I=1;$J=0;$J+=$I++until($I>10);print$J;#==>55perl-e"printwhile<>;"<readme.txt1Vine’sPerlStatements-- Perl语法：查看perlsyn网Commentsin#Thisistheperlstyle/*Cstyle*/isnotforperl,nor//C++sytleCommentoutblockofif(0)……somevalidperl}PoC(Plainold

ControlFlow#Multi-choice:##Multi-choice:#not"elseif"#not"elseif"#but"elsif"if(…)…}elsif(…)…}elsif(…)…}elsif(…)…}else…}0.000,0,undef,"0",(but"0.0""00"isif(…)if(…)…}else…}if(if(…)…}

Vine’sPerl##line200#theprevious'#'mustonthefirstdie'foo';#格式是顶格的'#'可选的空格行号"文件名 #comparemodifiedexpressionif#comparemodifiedexpressionif…;expressionunless…; ControlFlow

Vine’sPerl

ControlFlow

Vine’sPerlwhile until

my$var;

èjumptocontinueblockandcheckèjumptobeginningofloop,nocontinueblockorcond

foreach

foreach$var(@list) èexitloopimmedia##beforeloopwhile(##beforeloopwhile(…){… …redoifany;nextifany;lastifany;…

##beforeloopuntil(…){…

…don'tsplicethe@list#!Sideeffectofforeachforeach@array=(1..5,#!Sideeffectofforeachforeach@array=(1..5,foreach(@array) #Say'for(@L)…'isalso$_="Five"if($_==5);#defaultloopvaris}#foreachloopisfasterthanfor#1234556789#1234FiveFive6789#loopbefore#checkdo#loopbefore#checkdo…}until(…);#similartodo{}do…}while(…);#redo,next,lastnot

continue#run##…}

foreach$var(0..10){$var*=$var;}#non for(start_exp;for(start_exp;condition_exp;step_exp)…}

ControlFlow

Vine’sPerl

ControlFlow :last,next,redo,

Vine’sPerlAvoidgoto,alwayswritethe"goto-lessfor($n=1,$sum=0;$sum<=1000;$n++)$sum+=for($n=1,$sum=0;$sum<=1000;$n++)$sum+=}print"n=$n;$sum-=$n--print"n=$n;#n=46;#n=45;foreach$a(@list){INNERLOOP:while($b){nextINNERLOOPif(seeperlsynforSWITCH:

nextOUTERLOOPif}}if(/^abc/){$abc=1;lastSWITCH;}if(/^def/){$def=1;lastSWITCH;}if(/^xyz/){$xyz=1;lastSWITCH;}$nothing=} perlpod－Plain

Perl

Subroutine

Vine’sPerlMixedperlcodeand BeginwithLines'=pod_cmdEndwith'=cut'，i.e.returntoperlSomepodcommand=head1Yourheadline

参数在@_中，直接修改@_$_[i]Declarealllocalvariablesusingmy(…如果预先申明的函数,sub函数名Checkcontextwithwantarray()调用时,函数名可加前缀&(强烈不推荐),其中&foo相当=head2Yourheadlineover 项目列表开 项目列表结

sub$res=name($a,$b);@res=name$a,$b;subnamemy($arg1)=shift;my($arg2)=…

#pre 般没有必要预先#但先作函数申明或定义,调用函数时就可以省略括号#call#alsocansay&name($a,#definesubroutine#copyargumentspod过滤命令：pod2text

my($result,@result);#declarelocal……wantarray()?@result:$result;#return}9Vine’sPerl作业:

Subroutine

Vine’sPerl时，退出。附件名学号-提示:看Win32::Clipboard帮助下面是某次运行过程显示的结

Copyargumentsfrom@_(子程序 @_的内容subname #definemy$arg1=shiftmy$ary2=shift; #thesameasshift@_my($arg3,$arg4)=@_;#copyargumentsmy(@list)=@_; #orinthisformat…•Functionwithsideeffect,@_传递实际参数的别名subSide_effect$_[0]=$_[0]*ClipboardtextClipboardtext:"notethatyouClipboardtext:"#!/usr/bin/perl-wusestr"Clipboardnottext.Clipboardchangedtext:"Perl模块功能的些例子调用模use生成个剪贴板对my$Clip监视剪贴板变$Clip-$Clip-获得剪贴板的文本内$Clip-my$a=Side_effect($a);# es10Side_effect(5);#fatalrun-timeerror.5is"对@_作shift，不改变数组的元素，无副作" #!/usr/bin/perl-

Vine’sPerluseprint"10:\t",pi(10),print"100:\t",pi(100),print"1000:\t",pi(1000),print"10000:\t",pi(10000),

print"100000:\t",pi(100000),print :\t", ),subpimy($count)=$_[0];$inside+=sqr(rand1)+sqr(rand1)<1while$count-->0;4/$_[0]*}subsqrmy($n)=return$n*}Vine’sPerl算pi#!/usr/bin/perl-wusestrict;print"10:\t",pi(10),print"100:\t",pi(100),print"1000:\