RegexpGarden

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let garden = "Rose\tRosemary\tPrimrose\t

Rose\tRose\tPrimrose\t

Rosemary\tRose\tRose\t

Rosemary";

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garden = garden

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

Lesson 34 / 42

Lesson task •

Replace with blackberry all the roses that are followed directly by NOT rose

Negative Lookahead

/x(?!y)/ matches "x" only if it is directly followed by NOT "y"

Much alike Positive Lookahead, but do the opposite:

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console.log(!!"foobar".match(/foo(?!\d+)/gi)) // true

console.log(!!"foobar".match(/foo(?=\d+)/gi)) // false

console.log(!!"foo42".match(/foo(?!\d+)/gi)) // false

console.log(!!"foo42".match(/foo(?=\d+)/gi)) // true

console.log("foobar".replace(/foo(?!\d+)/gi, "bar")) // barbar

console.log("foobar".replace(/foo(?=\d+)/gi, "bar")) // foobar

console.log("foo42".replace(/foo(?!\d+)/gi, "bar")) // foo42

console.log("foo42".replace(/foo(?=\d+)/gi, "bar")) // bar42