# q operator creates a single-quoted string with any delimiter$q_string=q/This is a 'single-quoted' string/;print$q_string;# prints This is a 'single-quoted' string# qq operator creates a double-quoted string w
6|1if-else if($var==1){print"scalar";}elsif{$vareq'abc'}{#使用elsif,而不是elseifprint "string" }else{print'other';} 6|2三目运算符?: #和verilog的三目运算符一致my$name='Lisa';my$age='20';my$status= ($age>40) ?"is me":"not me";print"$name - $status\n"; 7|0循环(f...
# 对于字符串的相等,只能用eq (equal) 和 ne (not equal)。 } else { # 嗯,else还是和其他语言类似的 } foreach循环 # foreach循环其实有两种套路 # 普通的 my @arr = (a , b , c); foreach my $elem (@arr) { # 注意:my的使用,因为$elem前面没定义, # 所以这里必须定义用my。 # 其次,...
say 'the strings are not equal'; } The example compares two strings. $ ./comparison.pl the strings are not equal Perl string repeat Thexoperator repeats the given string. comparison.pl #!/usr/bin/perl use 5.30.0; use warnings; say 'falcon ' x 4; The example repeats the specified str...
splice运算符最多可以包含四个参数。 第一个参数是数组名,这里我们指定我们正在执行操作的数组 第二个参数是起点,如上所述,你可以在数组中间执行操作。这指定了操作的起点。 第三个参数是长度 第四个参数是另一个列表或数组。 让我们举几个例子来理解这个: ...
Remember that the width of the VARCHAR column # is the number of bytes set aside to store strings, which often does not equal # the number of characters it can hold when it comes to Unicode! $dbh->do("CREATE TABLE test( C_VARCHAR VARCHAR(100) )"); print OUTFILE "Inserting data.....
; if ($string =~ /World/) { print "Found 'World' in the string.\n"; } $new_string = s/World/Perl/; print "$new_string\n"; # 输出: Hello, Perl! 五、文件和目录操作Perl 提供了丰富的内置函数来处理文件和目录。打开和关闭文件: open(my $fh, '<', 'file.txt') or die "Could ...
$line =" multi line string/nhere" ; $line =~ m" multi line string" X; # this does not match the above because # the space above GETS MUNGED OUT. 1. 2. 3. 注意x可读性函数仅在替换运算符的第一个括号处起作用(也就是在s{}{}中)。这是因为只有第一个括号把它的值内插为一个双引字...
()-string not balanced sub snoid : Ugly('('); # ()-string not balanced sub xyzzy : 5x5; # "5x5" not a valid identifier sub plugh : Y2::north; # "Y2::north" not a simple identifier sub snurt : foo + bar; # "+" not a colon or space The attribute list is passed as ...
= inequality < less than > greater than <= less than or equal >= greater than or equal String comparison eq equality ne inequality lt less than gt greater than le less than or equal ge greater than or equal (Why do we have separate numeric and string comparisons? Because we don't ...