RegexpGarden

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let garden = "Rosemary\tRose\tPrimrose\t

Strawberry\tBlackberry\t

Rose\tBlackberry\t

Strawberry";

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garden = garden

.replace(//gi, "Blackberry");

Lesson 31 / 42

Lesson task •

Replace every rose or strawberry with blackberry

Disjunction

x|y matches either "x" or "y"

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console.log(!!"foo".match(/foo|bar/)) // true

console.log(!!"bar".match(/foo|bar/)) // true

console.log(!!"baz".match(/foo|bar/)) // false

To use a disjunction as part of the regular expression wrap it into a non-capturing group:

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console.log(!!"foo".match(/(?:foo|bar)42/)) // false

console.log(!!"foo42".match(/(?:foo|bar)42/)) // true

console.log(!!"bar".match(/(?:foo|bar)42/)) // false

console.log(!!"bar42".match(/(?:foo|bar)42/)) // true

console.log(!!"baz".match(/(?:foo|bar)42/)) // false

console.log(!!"baz42".match(/(?:foo|bar)42/)) // false

Fun fact: you can rewrite a custom symbol class with a disjunction: /(?:x|y)/ equals to /[xy]/:

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console.log(!!":".match(/[:;]/)) // true

console.log(!!":".match(/(?::|;)/)) // true

console.log(!!";".match(/[:;]/)) // true

console.log(!!";".match(/(?::|;)/)) // true

console.log(!!"4".match(/[:;]/)) // false

console.log(!!"4".match(/(?::|;)/)) // false

console.log(!!"f".match(/[:;]/)) // false

console.log(!!"f".match(/(?::|;)/)) // false

console.log(!!":::".match(/^[:;]$/)) // false

console.log(!!":::".match(/^(?::|;)$/)) // false