Check if a string contains a substring. Additionally, get index and number of match (Raku)

问题

FAQ: In Raku, how to check if a String contains a substring ? Where and how many times ? I would like 3 functions such as:

xxx-bool("az and az and az again", "az");  # True 
xxx-num("az and az and az again", "az");   # 3
xxx-list("az and az and az again", "az");  # (0 7 14) 

PS: Routines index and rindex are pretty cool but only get one match.

Related Links:

• Answer with Regex
• Answer on List (Array)
• Contiguous Sequences on List
• Answer on Hash (Dictionary)

回答1:

1. To check if it contains, use .contains to get a Bool which is a cool method.
2. To get indices (alias indexes: both are plural of index) use .indices
3. To get number, count the indices.

"az and az and az again".contains("az");        # True
"az and az and az again".indices("az").elems;   # 3
"az and az and az again".indices("az");         # (0 7 14)

PS: Routine indices is described just after index and rindex. So read the good doc, and read it well ;-)

• Links:

  • contains in regex
  • Same question in Python, Perl

来源：https://stackoverflow.com/questions/60853431/check-if-a-string-contains-a-substring-additionally-get-index-and-number-of-ma