Regular Expressions 101

Explanation

Pro

\:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 1((?:cons@(?:\d+(?:\.\d+)?|(?:"(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*")))|(?:[a-z]+(?:@[a-z]+)?|\^?[\~\&](?:[a-z]+|\d+|\-1)))

1st Alternative(?:cons@(?:\d+(?:\.\d+)?|(?:"(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*")))

Non-Capturing Group(?:cons@(?:\d+(?:\.\d+)?|(?:"(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*")))

cons@the literal text cons@ (case sensitive)

Non-Capturing Group(?:\d+(?:\.\d+)?|(?:"(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*"))

1st Alternative\d+(?:\.\d+)?

\d+a digit, repeated at least once

Non-Capturing Group(?:\.\d+)?

?repeats the group contents below at most once:

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

\d+a digit, repeated at least once

2nd Alternative(?:"(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*")

Non-Capturing Group(?:"(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*")

"the literal " (34₁₀ / 42₈ / 22₁₆)

Non-Capturing Group(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*

*repeats the group contents below any number of times:

1st Alternative(?:\\\\)+"

Non-Capturing Group(?:\\\\)+

+repeats the group contents below at least once:

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

"the literal " (34₁₀ / 42₈ / 22₁₆)

2nd Alternative[^"]

Negated Character Class[^"]

"the literal " (34₁₀ / 42₈ / 22₁₆)

3rd Alternative(?:\r\n|\r|\n)

Non-Capturing Group(?:\r\n|\r|\n)

1st Alternative\r\n

\ra carriage return (ASCII 13)

\na line-feed (newline) character (ASCII 10)

2nd Alternative\r

\ra carriage return (ASCII 13)

3rd Alternative\n

\na line-feed (newline) character (ASCII 10)

"the literal " (34₁₀ / 42₈ / 22₁₆)

2nd Alternative(?:[a-z]+(?:@[a-z]+)?|\^?[\~\&](?:[a-z]+|\d+|\-1))

Non-Capturing Group(?:[a-z]+(?:@[a-z]+)?|\^?[\~\&](?:[a-z]+|\d+|\-1))

1st Alternative[a-z]+(?:@[a-z]+)?

Character Class[a-z]+

+matches at least one character from the set below:

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

Non-Capturing Group(?:@[a-z]+)?

?repeats the group contents below at most once:

@the literal @ (64₁₀ / 100₈ / 40₁₆)

Character Class[a-z]+

+matches at least one character from the set below:

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

2nd Alternative\^?[\~\&](?:[a-z]+|\d+|\-1)

\^?optionally matches the literal ^ (94₁₀ / 136₈ / 5E₁₆)

Character Class[\~\&]

Non-Capturing Group(?:[a-z]+|\d+|\-1)

Global pattern flags

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

Match Information

Detailed match information will be displayed here automatically.

Quick Reference

25 tokens

Regular Expression

\:((?:cons@(?:\d+(?:\.\d+)?|(?:"(?:(?:\\\\)+"|[^"]|(?:\r\n|\r|\n))*")))|(?:[a-z]+(?:@[a-z]+)?|\^?[\~\&](?:[a-z]+|\d+|\-1)))

New

:define:&0:factorial
    :param:~0:static
    :case
        :lower@equal:cons@1
    :case:end
    :scope
        :return:cons@1
    :scope:end
    :scope
        :define:~0:static
        :define:~1:static
        :require:static
        :call:static@sub:^~0:~1 :store:~0
        :call:&-1:~0 :store:~1
        :call:static@sum:^~0:~1 :store:~0
        :return:~0
    :scope:end
:define:end

Substitution

:define:&0:factorial
    :param:~0:static
    :case
        :lower@equal:cons@1
    :case:end
    :scope
        :return:cons@1
    :scope:end
    :scope
        :define:~0:static
        :define:~1:static
        :require:static
        :call:static@sub:^~0:~1 :store:~0
        :call:&-1:~0 :store:~1
        :call:static@sum:^~0:~1 :store:~0
        :return:~0
    :scope:end
:define:end