regex101: define

Non-Capturing Group(?:is|are)?

?repeats the group contents below at most once:

1st Alternativeis

isthe literal text is (case sensitive)

2nd Alternativeare

arethe literal text are (case sensitive)

called the literal text called (case sensitive)

Character Class[a]?

?matches at most one character from the set below:

athe literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive)

Character Class[an]?

?matches at most one character from the set below:

athe literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive)

nthe literal n (110₁₀ / 156₈ / 6E₁₆) (case sensitive)

Character Class[its]?

?matches at most one character from the set below:

ithe literal i (105₁₀ / 151₈ / 69₁₆) (case sensitive)

tthe literal t (116₁₀ / 164₈ / 74₁₆) (case sensitive)

sthe literal s (115₁₀ / 163₈ / 73₁₆) (case sensitive)

\ban ASCII word boundary

?optionally matches the literal (32₁₀ / 40₈ / 20₁₆)

Group 1([^.|,|;]+)

Negated Character Class[^.|,|;]+

+matches at least one character outside the set below:

.the literal . (46₁₀ / 56₈ / 2E₁₆)

|the literal | (124₁₀ / 174₈ / 7C₁₆)

,the literal , (44₁₀ / 54₈ / 2C₁₆)

;the literal ; (59₁₀ / 73₈ / 3B₁₆)

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

26 tokens

Regular Expression

(?:is|are)? called [a]?[an]?[its]?\b ?([^.|,|;]+)

New

If we can prove a statement true, then that statement is called a proposition.

In studying abstract mathematics, we take what is called an axiomatic approach; that is, we take a collection of objects S and assume some rules about their structure. These rules are called axioms.

Sometimes instead of proving a theorem or proposition all at once, we break the proof down into modules; that is, we prove several supporting propositions, which are called lemmas, and use the results of these propositions to prove the main result

Regular Expressions 101

Regular Expression

Extraction