If Perl is installed, this command will display the version number. If Perl is not installed, you can install it using the package manager of your Linux distribution. For example, on Ubuntu, you can use the following command to install Perl: “` sudo apt-get install perl “` 2. Running...
1、push()、pop()和unshift()、shift() 这两组同为对数组的操作，并且会改变数组的本身的长度...
#!/usr/bin/perl # Function definition sub Average { # get total number of arguments passed. $n = scalar(@_); $sum = 0; foreach $item (@_) { $sum += $item; } $average = $sum/$n; print "Average for the given numbers : $average\n"; } # Function call Average(10, 20, 3...
my @colours= ("Red", "Orange", "Yellow", "Green", "Blue");my $arrayRef= \@colours;print $colours[0]; # direct array accessprint ${ $arrayRef }[0]; # use the reference to get to the arrayprint $arrayRef->[0]; # exactly the same thingmy %atomicWeights= ("Hydrogen" =>1.00...
则$text的内容为:"This text contains the number 11." .双引号内的字符串中支持转义字符 Table 3.1. Escape sequences in strings. Escape Sequence Description \a Bell (beep) \b Backspace \cn The Ctrl+n character \e Escape \E Ends the effect of \L, \U or \Q ...
Perl 诊断消息 类别含义 (W)警告(可选) (D)反对(可选) (S)严重警告(必需) (F)致命错误(可捕获) (P)你应该从未见过的内部错误(恐慌性的)(可捕获) (X)非常致命的错误(不可捕获) (A)外来错误消息(不是Perl生成的)
真正能使 c 程序员惊讶的是在 Perl 中,赋值语句返回实际的变量作为 lvalue.因此你 可以在同一个语句中多次 改变同一个变量的值.例如可以使用下面的语句: ($temp -= 32) *= 5/9 将华氏温度转换成摄氏温度.这也是为什么在本章的前面我们能使用下面的语句: chop ($number = ); 上面的语句能将 $number ...
if (@an_array) { print "has array elements\n" } if (%a_hash) { print "has hash members\n" } 又见undef 和 exists。 delete delete EXPR 这个函数从指定散列或者数组删除一个元素(或者一段元素)。(如果你想删除一个文件请参阅 unlink。)被删除的元素会按照声明它们的顺序返回,不过对捆绑的变量(...
win7系统，用c#调用Interop.SHDocVw.dll时，报了个对“ COM 组件的调用返回了错误 HRESULT E_FAIL”的...
When an array or slice is interpolated into a double-quoted string, this variable specifies the string to put between individual elements. Default is space. O(O(OSNAME) 存储平台名 !(!(ERRNO, $OS_ERROR) 数值上下文:最近一次调用的返回值 字符串上下文:响应系统错误信息 ,(,(OFS, $OUTPUT_FIE...