unicode-string-to-number.js

Google浏览器V8内核代码

// Copyright 2008 the V8 project authors. All rights reserved.
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// Make sure not to treat 16-bit unicode characters as ASCII
// characters when converting to numbers.
assertEquals(272, Number('2\u00372'));
assertTrue(isNaN(Number('2\u11372')), "short-string");

// Check that long string can convert to proper numbers.
var s = '\u0031';
for (var i = 0; i < 7; i++) {
  s += s;
}
assertTrue(isFinite(Number(s)));

// Check that long strings with non-ASCII characters cannot convert.
var s = '\u1131';
for (var i = 0; i < 7; i++) {
  s += s;
}
assertTrue(isNaN(Number(s)), "long-string");