lex - Regex with letter in range abcd at least once -

How do you write a regular expression that will return all the words in which each sequence character (such as ABCD) < P> Thanks!

thanks for using Lex with

 % {%} delim [\ t \ n] ws {delim} + lc [az] %% {ws} { / * No action taken * /} (? = {Lc} * a) (? = {Lc} * b) (? = {Lc} * c) (? = {Lc} * d) {/ * some code * /} %%    
 
 
 Using letterheads, the existence of all the letters in one word A simple pattern to check:  
  \ b (? = \ W * a) (? = \ W * b) (? = \ W * c) (? = \ W * D) \ w + \ b   
 instead of  ^ ... $  you want  \ b ... \ b  , If you want to  valid  the word  Capture , and you want to change the  \ w  in your acceptable alphabet.  
 Each  (? = \ W * a)  token has a look - it checks that the letter and a  a  are ahead, but not advance - The next situation is checked from  b , then start again.  
 For example:  
 See also:    
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