regex101: PCRE2 (PHP) Match Workspace

^start of string

\$the literal $ (36₁₀ / 44₈ / 24₁₆)

{the literal { (123₁₀ / 173₈ / 7B₁₆)

Group exp(?P<exp> (?: { (?P>exp) } # match object literal expression recursively |[^{}"']+ # simple eel expression without quoted strings |"[^"\\]* # double quoted strings with possibly escaped double quotes (?: \\. # escaped character (quote) [^"\\]* # unrolled loop following Jeffrey E.F. Friedl )*" |'[^'\\]* # single quoted strings with possibly escaped single quotes (?: \\. # escaped character (quote) [^'\\]* # unrolled loop following Jeffrey E.F. Friedl )*' )* )

Non-Capturing Group(?: { (?P>exp) } # match object literal expression recursively |[^{}"']+ # simple eel expression without quoted strings |"[^"\\]* # double quoted strings with possibly escaped double quotes (?: \\. # escaped character (quote) [^"\\]* # unrolled loop following Jeffrey E.F. Friedl )*" |'[^'\\]* # single quoted strings with possibly escaped single quotes (?: \\. # escaped character (quote) [^'\\]* # unrolled loop following Jeffrey E.F. Friedl )*' )*

*repeats the group contents below any number of times:

1st Alternative { (?P>exp) } # match object literal expression recursively

{ the literal text {

(?P>exp)calls group exp as a subroutine

} the literal text }

Comment: match object literal expression recursively

2nd Alternative[^{}"']+ # simple eel expression without quoted strings

Negated Character Class[^{}"']+

+matches at least one character outside the set below:

{the literal { (123₁₀ / 173₈ / 7B₁₆)

}the literal } (125₁₀ / 175₈ / 7D₁₆)

"the literal " (34₁₀ / 42₈ / 22₁₆)

'the literal ' (39₁₀ / 47₈ / 27₁₆)

Comment: simple eel expression without quoted strings

3rd Alternative"[^"\\]* # double quoted strings with possibly escaped double quotes (?: \\. # escaped character (quote) [^"\\]* # unrolled loop following Jeffrey E.F. Friedl )*"

"the literal " (34₁₀ / 42₈ / 22₁₆)

Negated Character Class[^"\\]*

*matches any number of characters outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

Comment: double quoted strings with possibly escaped double quotes

Non-Capturing Group(?: \\. # escaped character (quote) [^"\\]* # unrolled loop following Jeffrey E.F. Friedl )*

*repeats the group contents below any number of times:

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

.any character (except for line terminators)

Comment: escaped character (quote)

Negated Character Class[^"\\]*

*matches any number of characters outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

Comment: unrolled loop following Jeffrey E.F. Friedl

" the literal text "

4th Alternative'[^'\\]* # single quoted strings with possibly escaped single quotes (?: \\. # escaped character (quote) [^'\\]* # unrolled loop following Jeffrey E.F. Friedl )*'

'the literal ' (39₁₀ / 47₈ / 27₁₆)

Negated Character Class[^'\\]*

*matches any number of characters outside the set below:

'the literal ' (39₁₀ / 47₈ / 27₁₆)

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

Comment: single quoted strings with possibly escaped single quotes

Non-Capturing Group(?: \\. # escaped character (quote) [^'\\]* # unrolled loop following Jeffrey E.F. Friedl )*

*repeats the group contents below any number of times:

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

.any character (except for line terminators)

Comment: escaped character (quote)

Negated Character Class[^'\\]*

*matches any number of characters outside the set below:

'the literal ' (39₁₀ / 47₈ / 27₁₆)

\\the literal \ (92₁₀ / 134₈ / 5C₁₆)

Comment: unrolled loop following Jeffrey E.F. Friedl

' the literal text '

}the literal } (125₁₀ / 175₈ / 7D₁₆)

$end of string, or before its final line terminator

Global pattern flags

x modifier: extended. Ignores unescaped whitespace and comments outside character classes

Search reference

Regular Expression

^\${(?P<exp>
    (?:
      { (?P>exp) }          # match object literal expression recursively
      |[^{}"']+	            # simple eel expression without quoted strings
      |"[^"\\]*			    # double quoted strings with possibly escaped double quotes
        (?:
          \\.			# escaped character (quote)
          [^"\\]*		# unrolled loop following Jeffrey E.F. Friedl
        )*"
      |'[^'\\]*			# single quoted strings with possibly escaped single quotes
        (?:
          \\.			# escaped character (quote)
          [^'\\]*		# unrolled loop following Jeffrey E.F. Friedl
        )*'
    )*
  )}$

New

${abc abc abc abc abc abc abc abc abc abc abc ...'

Regular Expressions 101

Regular Expression

Substitution