NonSpaceChar ::= [#x21-#xD7FF] | [#xE000-#xFFFD]

Digit ::= [0-9]

Space ::= ' ' | '\t'

Numeric ::= (Digit* '.')? Digit+

BrowserName ::= 'ie'
  | 'edge'
  | 'firefox'
  | 'chrome'
  | 'safari'
  | 'opera'
  | 'ios_saf'
  | 'op_mini'
  | 'android'
  | 'bb'
  | 'op_mob'
  | 'and_chr'
  | 'and_ff'
  | 'ie_mob'
  | 'and_uc'
  | 'samsung'
  | 'and_qq'
  | 'baidu'
  | 'kaios'
  | 'fx'
  | 'ff'
  | 'ios'
  | 'explorer'
  | 'blackberry'
  | 'explorermobile'
  | 'operamini'
  | 'operamobile'
  | 'chromeandroid'
  | 'firefoxandroid'
  | 'ucandroid'
  | 'qqandroid'

CompareOperator ::= ('>' | '<') '='?

VersionKeyword ::= 'version' 's'?

LastBrowsers ::= 'last' Space+ Digit+ Space+ (BrowserName Space+)? ('major' Space+)? VersionKeyword

LastElectron ::= 'last' Space+ Digit+ Space+ 'electron' Space+ ('major' Space+)? VersionKeyword

LastNode ::= 'last' Space+ Digit+ Space+ 'node' Space+ ('major' Space+)? VersionKeyword

Unreleased ::= 'unreleased' Space+ ((BrowserName | 'electron') Space+)? VersionKeyword

Years ::= 'last' Space+ Numeric Space+ 'year' 's'?

Since ::= 'since' Space Digit+ ('-' Digit+ ('-' Digit+)?)?

Baseline ::= 'baseline' Space (Digit+ | ('newly' | 'widely') Space 'available' (Space 'on' Space Digit+ ('-' Digit+ ('-' Digit+)?)?)?) (Space 'with' Space 'downstream')? (Space 'including' Space 'kaios')?

Region ::= ('alt-' [a-z][a-z] | [A-Z][A-Z])

MyStats ::= 'my' Space+ 'stats'

CustomStats ::= NonSpaceChar+ Space+ 'stats'

Percentage ::= CompareOperator Space* Numeric '%' (Space+ 'in' Space+ (MyStats | CustomStats | Region))?

Cover ::= 'cover' Space+ Numeric '%' (Space+ 'in' Space+ (MyStats | Region))?

FeatureSupport ::= (('fully' | 'partially') Space+)? 'supports' Space+ ([a-z0-9] | '-')+

Version ::= (Digit | '.')+

BoundedRange ::= Version Space* '-' Space* Version

UnboundedRange ::= CompareOperator Space* Version

Electron ::= 'electron' Space+ (BoundedRange | UnboundedRange | Version)

Node ::= 'node' Space+ (BoundedRange | UnboundedRange | Version)

Browser ::= BrowserName Space+ (BoundedRange | UnboundedRange | Version | 'tp')

FirefoxESR ::= ('firefox' | 'fx' | 'ff') Space+ 'esr'

OperaMini ::= ('operamini' | 'op_mini') Space+ 'all'

CurrentNode ::= 'current' Space+ 'node'

MaintainedNode ::= 'maintained' Space+ 'node' Space+ 'versions'

Phantom ::= 'phantomjs' Space+ ('1.9' | '2.1')

BrowserslistConfig ::= 'browserslist config'

Extending ::= 'extends' Space NonSpaceChar+

Defaults ::= 'defaults'

Dead ::= 'dead'

QueryAtom ::= LastBrowsers
  | LastElectron
  | LastNode
  | Unreleased
  | Years
  | Since
  | Percentage
  | Cover
  | FeatureSupport
  | Electron
  | Node
  | Browser
  | FirefoxESR
  | OperaMini
  | CurrentNode
  | MaintainedNode
  | Phantom
  | BrowserslistConfig
  | Extending
  | Defaults
  | Dead

SingleQuery ::= ('not' Space)? QueryAtom

OrOperator ::= Space+ 'or' Space+ | Space* ',' Space*

AndOperator ::= Space+ 'and' Space+

BrowserslistQuery ::= QueryAtom ((OrOperator | AndOperator) SingleQuery)*

Root ::= BrowserslistQuery