What you are probably missing is that the "extended keys" generate multiple values for each keypress.

Below shows the output when four arrow keys are pressed in the order: left, right, up, down: 

use Term::ReadKey;;
{ 
    ReadMode(4); 
    print ord($c), " : '$c'" while ($c=ReadKey(0)) ne "\cM"; 
    ReadMode(0) 
};;
27  : '←'
91  : '['
68  : 'D'
27  : '←'
91  : '['
67  : 'C'
27  : '←'
91  : '['
65  : 'A'
27  : '←'
91  : '['
66  : 'B'

[download]

So, in order to match the left arrow key, you would need to use "\e[D" in your regex. But, ReadKey() returns those 3 characters one at a time, so you would need to accumulate them before you could match that.

But then the problem becomes how do you decide when you see the escape character (←, '←', "\e"; 27), whether the user has pressed the escape key, or some other keys that also generates more characters.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Regex arrow key problem by BrowserUk
in thread Regex arrow key problem by austin43

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