Bash and textarea checking

Recently i got a task to write a simple javascript checking of the textarea field which can be filled with maximum 250 chars.

I wrote a regular expression /^.{0, 250}$/ and where can take quickly an example of text with 250 chars?

Simple Bash script was a quick decision:
for i in {1..250}; do echo -ne "a"; done

Just wondered again how it is cool.