Regular Expressions 101

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  • Unit Tests (17)

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Generated Code

$re = '/(?:(?<=(?:import|export)[^`\'"]*from\s+[`\'"])(?<path1>[^`\'"]+)(?=(?:\'|"|`)))|(?:\b(?:import|export)(?:\s+|\s*\(\s*)[`\'"](?<path2>[^`\'"]+)[`\'"])/m'; $str = 'import { defaultTemplateProcessor } from \'./lib/default-template-processor.js\'; import { SVGTemplateResult, TemplateResult } from \'./lib/template-result.js\'; export { DefaultTemplateProcessor, defaultTemplateProcessor } from \'./lib/default-template-processor.js\'; export { directive, isDirective } from \'./lib/directive.js\'; export { removeNodes, reparentNodes } from \'./lib/dom.js\'; export { noChange, nothing } from \'./lib/part.js\'; export { AttributeCommitter, AttributePart, BooleanAttributePart, EventPart, isIterable, isPrimitive, NodePart, PropertyCommitter, PropertyPart } from \'./lib/parts.js\'; export { parts, render } from \'./lib/render.js\'; export { templateCaches, templateFactory } from \'./lib/template-factory.js\'; export { TemplateInstance } from \'./lib/template-instance.js\'; export { SVGTemplateResult, TemplateResult } from \'./lib/template-result.js\'; export { createMarker, isTemplatePartActive, Template } from \'./lib/template.js\'; import { render } from \'lit-html/lib/shady-render.js\'; import { UpdatingElement } from \'./lib/updating-element.js\'; export * from \'./lib/updating-element.js\'; export * from \'./lib/decorators.js\'; export { html, svg, TemplateResult, SVGTemplateResult } from \'lit-html/lit-html.js\'; import { supportsAdoptingStyleSheets } from \'./lib/css-tag.js\'; export * from \'./lib/css-tag.js\'; import { LitElement } from \'lit-element\'; import { IronMeta } from \'@polymer/iron-meta/iron-meta.js\'; import { whenOnline } from \'hadron-core/lib/utils/async.js\'; import { apiUrl, apiVersion } from \'../../src/config.js\'; import { importModule, dynamicImportAvailable } from \'../../src/dynamic-imports-polyfill.js\'; import observeProperties from \'hadron-core/lib/utils/object-property-observer.js\'; export { version }; import { ElementMixin, version } from \'./lib/mixins/element-mixin.js\'; export { html } from \'./lib/utils/html-tag.js\'; class Foo { constructor() { import(`foo.js`); import(`${foo}`); import(\'bar.js\'); } }'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php