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// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 21.1.3.18
description: >
Returns true if searchString appears as a substring of the given string with a
given position.
info: |
21.1.3.18 String.prototype.startsWith ( searchString [ , position ] )
...
11. Let len be the number of elements in S.
12. Let start be min(max(pos, 0), len).
13. Let searchLength be the number of elements in searchStr.
14. If searchLength+start is greater than len, return false.
15. If the sequence of elements of S starting at start of length searchLength
is the same as the full element sequence of searchStr, return true.
...
---*/
var str = 'The future is cool!';
assert(
str.startsWith('The future', 0),
'str.startsWith("The future", 0) === true'
);
assert(
str.startsWith('future', 4),
'str.startsWith("future", 4) === true'
);
assert(
str.startsWith(' is cool!', 10),
'str.startsWith(" is cool!", 10) === true'
);
reportCompare(0, 0);
|
