Regular Expressions 101

Explanation
Pro

{the literal { (123₁₀ / 173₈ / 7B₁₆)

\s+any whitespace character, repeated at least once

"last_name":the literal text "last_name": (case sensitive)

\s+any whitespace character, repeated at least once

"?optionally matches the literal " (34₁₀ / 42₈ / 22₁₆)

Group 1([^"]+)

Negated Character Class[^"]+

+matches at least one character outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

"?optionally matches the literal " (34₁₀ / 42₈ / 22₁₆)

,the literal , (44₁₀ / 54₈ / 2C₁₆)

\s+any whitespace character, repeated at least once

"id":the literal text "id": (case sensitive)

\s+any whitespace character, repeated at least once

Group 2(\d+)

\d+a digit, repeated at least once

,the literal , (44₁₀ / 54₈ / 2C₁₆)

\s+any whitespace character, repeated at least once

"first_name":the literal text "first_name": (case sensitive)

\s+any whitespace character, repeated at least once

"?optionally matches the literal " (34₁₀ / 42₈ / 22₁₆)

Group 3([^"]+)

Negated Character Class[^"]+

+matches at least one character outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

"?optionally matches the literal " (34₁₀ / 42₈ / 22₁₆)

\s+any whitespace character, repeated at least once

}the literal } (125₁₀ / 175₈ / 7D₁₆)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

No unit tests

Add a test to get started

25 tokens

{\s+"last_name":\s+"?([^"]+)"?,\s+"id":\s+(\d+),\s+"first_name":\s+"?([^"]+)"?\s+}

There are no unit tests.