Regx - Declarative Regex for humans

F# DSL for Regex nuget

#r "nuget: Regx"
open Regx

// Compose a regex for url 

let protocol =
    group {
        capture {
            oneOf {
                verbatimString "http"
                verbatimString "https"
            }
        }
        verbatimString "://"
    }

let subdomain =
    group {
        oneOrMore { wordChar }
        verbatimString "."
    }

let domain =
    group {
        captureAs "domain" { occursBetween 2 256 { wordChar } }
        verbatimString "."
    }

let ending = group { occursBetween 1 8 { wordChar } }

let port =
    group {
        verbatimString ":"
        occursMoreThan 2 { digit }
    }

let path =
    zeroOrMore {
        capture {
            verbatimString "/"
            oneOrMore { wordChar }
        }
    }

let pattern =
    regex {
        mayHave { protocol }
        mayHave { subdomain }
        domain
        ending
        mayHave { port }
        path
    }
    |> Regx.make

// Generates - (?:(http|https):\/\/)?(?:\w+\.)?(?:(?<domain>\w{2,256})\.)(?:\w{1,8})(?::\d{2,})?(\/\w+)*

More examples in tests

DSL	What it means
any	Dot - Matches any character except linebreaks. Equivalent to [^\n\r].
anyChar	Match any - A character set that can be used to match any character, including line breaks, without the dotall flag. Represents [\s\S]
wordChar	Matches any word character (alphanumeric & underscore). Only matches low-ascii characters (no accented or non-roman characters). Equivalent to [A-Za-z0-9_]
notWordChar	Matches any character that is not a word character (alphanumeric & underscore). Equivalent to [^A-Za-z0-9_]
digit	Matches any digit character (0-9). Equivalent to [0-9].
notDigit	Matches any character that is not a digit character (0-9). Equivalent to [^0-9].
whiteSpace	Matches any whitespace character (spaces, tabs, line breaks).
notWhiteSpace	Matches any character that is not a whitespace character (spaces, tabs, line breaks).
charIn	Match any character in the set
charNotIn	Negate character set - Match any character that is not in the set.
inRange	Matches a character having a character code between the two specified characters inclusive.
inList	Matches characters in list
beginsWith	Enclosed expression occurs in the beginning of the fragment
endsWith	Enclosed expression occurs in the end of the fragment
beginsWithString	Enclosed expression occurs in the beginning of the fragment
endsWithString	Enclosed expression occurs in the end of the fragment
wordBoundary	Matches a word boundary position between a word character and non-word character or position (start / end of string).
notWordBoundary	Matches any position that is not a word boundary. This matches a position, not a character.
mayHave	Matches 0 or 1 of the enclosed fragment, effectively making it optional
fewest	Makes the enclosed fragment lazy, causing it to match as few characters as possible.
longest	Makes the enclosed fragment Greedily, causing it to match as many characters as possible.
oneOf	Acts like a boolean OR. Matches the expression before or after the
oneOrMore	Matches 1 or more of the enclosed fragment
zeroOrMore	Matches 0 or more of the enclosed fragment
occurs	Matches the exact quantity of the enclosed token.
occursMoreThan	Matches the specified quantity or more of the enclosed token.
occursBetween	Matches a quantity of the enclosed toke in the specified range.
between	Match between an open and a closing tag- for balanced captures
capture	Grouped capture
captureAs	Named group capture
group	Non-capturing group
refGroupNo	\1 - Numeric reference - Matches the results of a capture group.
refGroupName	\k - Group name reference - Matches the results of a named capture group.
positiveLookAhead	\d(?=px) - Matches a group after the main expression without including it in the result.
negativeLookAhead	\d(?!px) - Specifies a group that can not match after the main expression (if it matches, the result is discarded).
positiveLookBehind	(?<=ABC) - Matches a group before the main expression without including it in the result.
negativeLookBehind	(?<!ABC) - Specifies a group that can not match before the main expression (if it matches, the result is discarded).
verbatimString	Unescaped string literal
tab
lineFeed
verticalTab
formFeed
carriageReturn
nullCharacter

Additional custom builders

DSL	What it means
word	Represents an actual word. Equivalent to /(?:\w+)/
email	English email
url	English url
guid	GUID
uuid	UUID
ip4Address	IPv4
ip6Address	IPv6
ipAddress	IPV4 or IPv6 (does not support embedded IPv4 address)