- Usually define a regex by placing it inside two
/
/abc/- The
/ are delimiters, which tell us we are using a regex.
- The
/ is not part of the expression, they are the delimiters that hold it.
- Most of the time, the
/ are not used.
- The
/ is to contrast it again the text strings that are being used to match it.
- With the above example, the characters
abc are going to match a text string called "abc"
- With our javascript tool, we use those text strings without quotes.
- Expression Flags
- Indicates different modes that are used with the regex.
- Standard:
/re/
- Global:
/re/g
- Match this over and over again throughout the document.
- Find all the matches and look globally.
- If this isn’t used, it will only look for the first match.
- Case Insensitive:
/re/i
- Multiline:
/re/m
- Can our regular expression match text that stretches across more than 1 line.
- By default, regex cannot span more than 1 line.
grep gets its name from g/re/p
- The global flag used to be at the beginning for regex, that’s why it uses
g at the front.
- This stood for
Global Regular Expression Print