How to remove all characters from a string, except the integers?

[bachmeier]

On Thursday, 3 March 2022 at 13:55:47 UTC, BoQsc wrote:
> On Thursday, 3 March 2022 at 13:25:32 UTC, Stanislav Blinov 
> wrote:
>> On Thursday, 3 March 2022 at 12:14:13 UTC, BoQsc wrote:
>>
>>> I need to check if a string contains integers,
>>> and if it contains integers, remove all the regular string 
>>> characters.
>>> I've looked around and it seems using regex is the only 
>>> closest solution.
>>
>> ```d
>> import std.stdio;
>> import std.algorithm : find, filter;
>> import std.conv : to;
>> import std.uni : isNumber;
>>
>> void main(string[] args){
>>     if (args.length > 1){
>> 	
>>         auto filtered = () {
>>             auto r = args[1].find!isNumber; // check if a 
>> string contains integers
>>             return r.length ?
>>                    r.filter!isNumber.to!string // and if it 
>> does, keep only integers
>>                    : args[1];                  // otherwise 
>> keep original
>>         } ();
>>
>>         filtered.writeln;
>> 		
>>     } else {
>>         write("Please write an argument.");
>>     }
>> }
>> ```
>
> D language should be renamed into Exclamation-mark language.
> It feels overused everywhere and without a better alternative.

But you have no problem with parenthesis and braces?