extract substring until first digit

Question

I have the following string:

test1234a or test1234 for example and I want to extract only test from that string.

I tried the follwing

echo "Test12h" | sed -e 's/[0-9]\*$//' but is not working. 

Is there any possibility to extract the substring until first digit?

Please let me know what I miss.

Thank you

Answer 1

The proper tool for extracting substrings matching a regexp from a command's output is grep. Like,

echo "Test12h" | grep -o '^[^[:digit:]]*'

will output Test.

If Test12h is in a variable, you don't even need external utilities; parameter expansions can easily handle that, e.g:

var='Test12h'
echo "${var%%[[:digit:]]*}"