JavaScript: The Definitive Guide, Sixth Editio javaScript权威指南(第6版) pdf 文字版-文字版, javascript电子书, 和javascript 有关的电子书:

Unlike many languages, JavaScript does not make a distinction between integer values#### 3.1 Numbers

and floating-point values. All numbers in JavaScript are represented as floating-point

values. JavaScript represents numbers using the 64-bit floating-point format defined

by the IEEE 754 standard,

1

which means it can represent numbers as large as

±1.7976931348623157 × 10308 and as small as ±5 × 10−324.

The JavaScript number format allows you to exactly represent all integers between

−9007199254740992 (−253) and 9007199254740992 (253), inclusive. If you use integer

values larger than this, you may lose precision in the trailing digits. Note, however, that

certain operations in JavaScript (such as array indexing and the bitwise operators de-

scribed in Chapter 4) are performed with 32-bit integers.

When a number appears directly in a JavaScript program, it’s called a numeric literal.

JavaScript supports numeric literals in several formats, as described in the following

sections. Note that any numeric literal can be preceded by a minus sign (-) to make the

number negative. Technically, however, - is the unary negation operator (see Chap-

ter 4) and is not part of the numeric literal syntax.

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