Find matches

2 snippets in Regular Expressions

Also written as find all matches

RXRegular Expressions

g - Global Flag

syntax

JS: /pattern/g    Python: (default for findall/sub)

example

JS:  'aaa'.match(/a/g)
JS:  'aaa'.match(/a/)   // without g
Py:  re.findall(r'a', 'aaa')  # global by nature

output

With g: ["a", "a", "a"]
Without g: ["a"] (first match only)
Python findall: ['a', 'a', 'a']

Note In JS, the g flag makes match() return all matches instead of just the first. Without g, match() returns the first match with capture groups. Python's re.findall and re.sub are inherently global. Use re.search for first-match-only behavior in Python.

JS: match() - Find Matches

RX · String Operations with Regex

syntax

string.match(/pattern/)  or  string.match(/pattern/g)

example

// Without g: returns first match + groups
'Price: $42.99'.match(/(\$)(\d+\.\d{2})/)
// With g: returns all matches (no groups)
'$42.99 and $18.50'.match(/\$\d+\.\d{2}/g)

output

Without g: ["$42.99", "$", "42.99"]
With g: ["$42.99", "$18.50"]

Note Behavior changes completely depending on the g flag. Without g, you get detailed info (groups, index). With g, you get a flat array of all matches but lose group details. Use matchAll for both multiple matches AND group info.