Regular Expressions 101

\ban ASCII word boundary

Positive Lookahead(?=[a-zA-Z]*e)

Character Class[a-zA-Z]*

*matches any number of characters from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

ethe literal e (101₁₀ / 145₈ / 65₁₆) (case sensitive)

Positive Lookahead(?=[a-zA-Z]*(.)\1)

Character Class[a-zA-Z]*

*matches any number of characters from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

Group 1(.)

.any character (except for line terminators)

\1the text saved by group 1

Character Class[a-zA-Z]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

A-Zone character from A (65₁₀) to Z (90₁₀) (case sensitive)

\ban ASCII word boundary

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

\b(?=[a-zA-Z]*e)(?=[a-zA-Z]*(.)\1)[a-zA-Z]+\b

New

It’s not artificial intelligence it’s a charismatic mistake machine. Specific LLMs and neural networks can be trained to be really good at pre-defined tasks, but in general they are only really good at doing tasks that have already been done 300 million times, and terrible at new and novel tasks. Any time there’s limited training data it either plagiarizes or is totally wrong.