Ask help for Perl sort customized function

[Fangyuan]

大家好，请教一个自定义sort函数的问题。

有一个数组，@a = (1..20, "10+")，我想对这个数组排序，排序的规则是：1）数字优先， "10+"排在数字后面；2）数字按从小到大

我自己写了一个代码，运行没有返回我想要的结果。寻求高手指点一下，谢谢！

my @a = (0..20, "10+");

my @b = sort{

if(m/^\d+$/){

return $a <=> $b;

}

else{

return -1;

}

} @a;

print join(",", @b), "\n";

[Fayland Lam]

try this.

my @a = (0..20, "10+", 21 .. 25);
@a = reverse(@a);
my @b = sort{
if($a =~ /^\d+$/ and $b =~ /^\d+$/){
return $a <=> $b;
} elsif ($a =~ /^\d+$/) {
return -1;
} elsif ($b =~ /^\d+$/) {
return 1;
} else {
return $a cmp $b;

}
} @a;
print join(",", @b), "\n";

if you have

use warnings;

it will tell you that

Use of uninitialized value $_ in pattern match (m//)

then you know there isn't $_ in sort {}

Thanks

2011/9/19 Fangyuan <chengfan...@gmail.com>:

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--
Fayland Lam // http://www.fayland.org/

[Robin Lee]

my @b = sort{
if ($a !~ /^\d+$/) {
return 1;
}
elsif ($b !~ /^\d+$/) {
return -1;
}
else {
return $a <=> $b;
}
} @a;

2011/9/19 Fangyuan <chengfan...@gmail.com>:

[Fangyuan]

It works.

Thanks Fayland and Cheese.