Both work fundamentally the same way, at compile time the keyword "var" is replaced with the correct scalar or array type for the associated expression.

二者的实现基础完全相同，即在编译时将“var”替换成为分析得到的正确的变量或数组类型表达式。

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This does not apply to the comma separator, which is used in object literals, array literals, var statements, and parameter lists.

这不包括那些被用在对象定义，数组定义，var语句，和参数列表中的逗号分隔符。

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