Regex to match if a word starts and end with a letter, have no more than one consecutive non-letter (. *')

Question

I'm currently trying to find a regex to match a specific use case and I'm not finding any specific way to achieve it. I would like, as the title says, to match if a word starts and end with a letter, contains only letter and those characters: "\ *- \'" . It should also have no more than one consecutive non-letter.

I currently have this, but it accepts consecutive non-letter and doesn't accept single letters [a-zA-Z][a-zA-Z \-*']+[a-zA-Z]

I want my regex to accept this string

• This is accepted since it contains only spaces and letter and there is no consecutive space

• a should be accepted

• This is --- not accepted because it contains 5 consecutive non-letters characters (3 dashes and 2 spaces)

• " This is not accepted because it starts with a space"

• Neither is this one since it ends with a dash -

Answer 1

You may use

^[a-zA-Z]+(?:[ *'-][a-zA-Z]+)*$

See the regex demo and the regex graph:

Details

• ^ - start of string anchor
• [a-zA-Z]+ - 1+ ASCII letters
• (?:[ *'-][a-zA-Z]+)* - 0 or more sequences of:
  • [ *'-] - a space, *, ' or -
  • [a-zA-Z]+ - 1+ ASCII letters
• $ - end of string anchor.