On Thursday, 3 March 2022 at 12:14:13 UTC, BoQsc wrote:
> I've looked around and it seems using regex is the only closest solution.

I'm a simple man who uses D with the old C mentality:

import std.stdio;

void main(){
    string s, str = "4A0B1de!2C9~6";
    foreach(i;str){
        if(i < '0' || i > '9'){ continue; }
        s ~= i;
    }
    writeln("Result: ", s);
}

Result: 401296

Matheus.

On Thursday, 3 March 2022 at 19:28:36 UTC, matheus wrote:
>
> I'm a simple man who uses D with the old C mentality:
>
> import std.stdio;
>
> void main(){
>     string s, str = "4A0B1de!2C9~6";
>     foreach(i;str){
>         if(i < '0' || i > '9'){ continue; }
>         s ~= i;
>     }
>     writeln("Result: ", s);
> }
>
> Result: 401296
>
> Matheus.

mmm..but we no longer live in simple times ;-)

(i.e. unicode)

On Thu, Mar 03, 2022 at 08:23:14PM +0000, forkit via Digitalmars-d-learn wrote:
> On Thursday, 3 March 2022 at 19:28:36 UTC, matheus wrote:
> > 
> > I'm a simple man who uses D with the old C mentality:
> > 
> > import std.stdio;
> > 
> > void main(){
> >     string s, str = "4A0B1de!2C9~6";
> >     foreach(i;str){
> >         if(i < '0' || i > '9'){ continue; }
> >         s ~= i;
> >     }
> >     writeln("Result: ", s);
> > }
> > 
> > Result: 401296
> > 
> > Matheus.
> 
> mmm..but we no longer live in simple times ;-)
> 
> (i.e. unicode)

------
void main() {
	string s = "blahblah123blehbleh456bluhbluh";
	auto result = s.filter!(ch => ch.isDigit).to!int;
	assert(result == 123456);
}
------

Problem solved.  Why write 6 lines when 3 will do?


T

-- 
People tell me that I'm skeptical, but I don't believe them.

On Thursday, 3 March 2022 at 21:03:40 UTC, H. S. Teoh wrote:
> ...
>
> ------
> void main() {
> 	string s = "blahblah123blehbleh456bluhbluh";
> 	auto result = s.filter!(ch => ch.isDigit).to!int;
> 	assert(result == 123456);
> }
> ------
>
> Problem solved.  Why write 6 lines when 3 will do?

Just because I'm a simple man. :)

I usually program mostly in C and when in D, I go in the same way but using features like: GC, strings, AA etc.

Of course your version is a D'ish way of handling things, and I can't contest it looks better visually. But if size was problem I could have written:

void main(){
    string s, str = "4A0B1de!2C9~6";
    foreach(i;str){
    	(i >= '0' && i <= '9') ? s~=i : null;
    }
    writeln(s);
}

Well still 1 line off, but I goes with my flow. I mean this example is a simple one, but usually I can see and understand what a code in C is doing (more) easily than D just looking at it. Don't even ask about C++, because I gave up. :)

Matheus.

PS: I spotted something on your code, you're converting the result to int, this can lead to a overflow depending the values in the string.

On Thu, Mar 03, 2022 at 10:54:39PM +0000, matheus via Digitalmars-d-learn wrote:
> On Thursday, 3 March 2022 at 21:03:40 UTC, H. S. Teoh wrote:
[...]
> > ------
> > void main() {
> > 	string s = "blahblah123blehbleh456bluhbluh";
> > 	auto result = s.filter!(ch => ch.isDigit).to!int;
> > 	assert(result == 123456);
> > }
> > ------
[...]
> PS: I spotted something on your code, you're converting the result to int, this can lead to a overflow depending the values in the string.

If you need to, convert to long instead.

Or if you want a string for subsequent manipulation, replace `int` with `string`.

Or, if you don't actually need to manipulate the value at all, but just print the digits, then it becomes even simpler:

	void main() {
		string s = "blahblah123blehbleh456bluhbluh";
		writeln(s.filter!(ch => ch.isDigit));
	}

This version doesn't even allocate extra storage for the filtered digits, since no storage is actually needed (each digit is spooled directly to the output).


T

-- 
The peace of mind---from knowing that viruses which exploit Microsoft system vulnerabilities cannot touch Linux---is priceless. -- Frustrated system administrator.