Spinal Tap solved, but I still don't understand regexp

1

My code that solves the challenge below:

function spinalCase(str) {
 	var regExp = /[^-_\s][a-z]*/g; // exclude '-','_',whitespace
  var result = [];
  var words = str.match(regExp);
  var wordCount = words.length;
  
  for (var i = 0; i < wordCount; i++) {
    if ( i < wordCount - 1) {
      result.push ( words[i] + '-');
    }
    else {
      result.push( words[i] );
    }
  }
  return result.join("").toLowerCase();
}

I used the online regex tools from here, but the part I do not understand is how is [a-z] including whole words that begin with an uppercase letter? To me, my regex pattern shouldn’t even be working yet it apparently satisfies the challenge.

2

The first part matches anything that is not a dash, underscore, or whitespace. Uppercase characters would be selected by that.

2 Likes
3

I think I understand what you mean, and [a-z]* that follows I am saying the 2nd letter in the matching expression must be zero or more occurrences of a lowercase letter? I think is what I am doing here.

4

Yup, that’s it. :+1: