It seems a little misleading to write "Which one of these snippets would you like to encounter within your source code" and then go on to compare the generated

It seems a little misleading to write "Which one of these snippets would you like to encounter within your source code" and then go on to compare the generated regex code with the hand-written builder code. The generated regex is much uglier, more redundant, and more complex than what a person familiar with the syntax would write (e.g. grandparent's example regex). Also, does the builder library support captures (i.e. pulling out substrings that match subpatterns)? That is a pretty important feature for a regex library.