JavaScript's ASI is a feature that can automatically insert semicolons at the end of certain statements if they are missing. This can be useful in some cases, but it can also lead to bugs.
ASI is applied to the following types of statements:
The specific rules for ASI are as follows:
If an invalid token is encountered that is not allowed by the grammar, a semicolon is inserted before it if:
Restricted productions include:
Example 1:
{ 1 2 } 3
ASI will transform this code to:
{ 1 ;2 ;} 3;
Example 2:
a = b ++c
ASI will transform this code to:
a = b; ++c;
Example 3:
return "something";
ASI will transform this code to:
return; "something";
ASI can be a useful feature, but it can also lead to bugs. To avoid ASI bugs, it is best to always use semicolons explicitly at the end of each statement.
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