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// Copyright 2019 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
namespace string {
// ES6 #sec-string.prototype.substring
transitioning javascript builtin StringPrototypeSubstring(
js-implicit context: NativeContext, receiver: JSAny)(...arguments): String {
// Check that {receiver} is coercible to Object and convert it to a String.
const string: String = ToThisString(receiver, 'String.prototype.substring');
const length: uintptr = string.length_uintptr;
// Conversion and bounds-checks for {start}.
const arg0 = arguments[0];
let start: uintptr = arg0 != Undefined ? ClampToIndexRange(arg0, length) : 0;
// Conversion and bounds-checks for {end}.
const arg1 = arguments[1];
let end: uintptr =
arg1 != Undefined ? ClampToIndexRange(arg1, length) : length;
if (end < start) {
const tmp: uintptr = end;
end = start;
start = tmp;
}
return SubString(string, start, end);
}
}
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