###Compatibility with Express <= 4.x

Path-To-RegExp breaks compatibility with Express <= 4.x:

• No longer a direct conversion to a RegExp with sugar on top - it’s a path matcher with named and unnamed matching groups
• It’s unlikely you previously abused this feature, it’s rare and you could always use a RegExp instead
• All matching RegExp special characters can be used in a matching group. E.g. /:user(.*)
• Other RegExp features are not support - no nested matching groups, non-capturing groups or look aheads
• Parameters have suffixes that augment meaning - , + and ?. E.g. /:user

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