Skip to content
Permalink
9bfb9ba527
Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
Go to file
 
 
Cannot retrieve contributors at this time
31 lines (30 sloc) 993 Bytes
/**
* Extractor function for a UnaryExpression type value node.
* A unary expression is an expression with a unary operator.
* For example, !"foobar" will evaluate to false, so this will return false.
*
* @param - value - AST Value object with type `UnaryExpression`
* @returns - The extracted value converted to correct type.
*/
export default function extractValueFromUnaryExpression(value) {
// eslint-disable-next-line global-require
const getValue = require('.').default;
const { operator, argument } = value;
switch (operator) {
case '-':
return -getValue(argument);
case '+':
return +getValue(argument); // eslint-disable-line no-implicit-coercion
case '!':
return !getValue(argument);
case '~':
return ~getValue(argument); // eslint-disable-line no-bitwise
case 'delete':
// I believe delete statements evaluate to true.
return true;
case 'typeof':
case 'void':
default:
return undefined;
}
}