[Javascript] How to insert line number automatically for debug

1. add “Line # 999 \n” to each line in the script that you want numbered, e.g.,
   alert ( “Line # 999 \n”);
   
2. run the perl below:
   cat my_js.js | perl -ane “{ s/Line # \d+ /Line # $. /; print$_;}” > C_my_js.js; mv C_my_js.js my_js.js

Reference:

• LINE equivalent in Javascript