Hello all.
I want to write a regex to check if a whole string is a number.
With my current regex("[0-9]+") numbers will be carved out of things like
"aaa456" (hit: 456) and I circumvent this by checking the lengths for
inequality, which is stupid. My regex is surely missing something?

Thank you for reading.

> I want to write a regex to check if a whole string is a number.
> With my current regex("[0-9]+") numbers will be carved out of things like
> "aaa456" (hit: 456) and I circumvent this by checking the lengths for
> inequality, which is stupid. My regex is surely missing something?

Try ^ and $ if applicable. These match start and end of a line.

On Tue, 31 Jan 2012 16:29:43 +0000, NewName wrote:

> Hello all.
> I want to write a regex to check if a whole string is a number. With my
> current regex("[0-9]+") numbers will be carved out of things like
> "aaa456" (hit: 456) and I circumvent this by checking the lengths for
> inequality, which is stupid. My regex is surely missing something?
> 
> Thank you for reading.

You want to match the beginning and end of the input as well: "^[0-9]+$"

> You want to match the beginning and end of the input as well: "^[0-9]+$"

Thanks.

NewName:

> Hello all.
> I want to write a regex to check if a whole string is a number.

Also:

import std.stdio, std.string, std.array;
void main() {
    string s = "123";
    assert(s.removechars("0-9").empty);
}

Bye,
bearophile