Regular Expressions 101

Pro

1st Alternative\\begin\{(\w+)\}.*?\\end\{\1\}

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

beginthe literal text begin (case sensitive)

\{the literal { (123₁₀ / 173₈ / 7B₁₆)

Group 1(\w+)

\w+any word character, repeated at least once

\}the literal } (125₁₀ / 175₈ / 7D₁₆)

.*?any character, repeated any number of times

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

endthe literal text end (case sensitive)

\{the literal { (123₁₀ / 173₈ / 7B₁₆)

\1the text saved by group 1

\}the literal } (125₁₀ / 175₈ / 7D₁₆)

2nd Alternative\\(?!begin|end)\w+\{\w+\}

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

Negative Lookahead(?!begin|end)

1st Alternativebegin

beginthe literal text begin (case sensitive)

2nd Alternativeend

endthe literal text end (case sensitive)

\w+any word character, repeated at least once

\{the literal { (123₁₀ / 173₈ / 7B₁₆)

\w+any word 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

s modifier: single line. Allows a dot to match line terminators

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

\\begin\{(\w+)\}.*?\\end\{\1\}|\\(?!begin|end)\w+\{\w+\}

New

\questao{1}

\begin{enumerate}
esse não
\end{enumerate}

\begin{enumerate}
esse sim
\begin{enumerate}
enumerate dentro de outro, não funciona
\end{enumerate}
\end{enumerate}

\questao{2}

\begin{enumerate}
esse também não
\end{enumerate}

\begin{enumerate}
esse também sim
\end{enumerate}

\questao{3}