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'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = extractValueFromUnaryExpression;
/**
* 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.
*/
function extractValueFromUnaryExpression(value) {
// eslint-disable-next-line global-require
var getValue = require('.').default;
var operator = value.operator,
argument = value.argument;
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;
}
}