src/sign.js
function sign(value) {
    let sign = NaN;

    if (_.isNumber(value)) {
        if (value === 0) {
            sign = value;
        }
        else if (value >= 1) {
            sign = 1;
        }
        else if (value <= -1) {
            sign = -1;
        }
    }

    return sign;
}
function sign(value) {
    let sign = NaN;

    if (_.isNumber(value)) {
        if (value === 0) {
            sign = value;
        }
        else if (value >= 1) {
            sign = 1;
        }
        else if (value <= -1) {
            sign = -1;
        }
    }

    return sign;
}
function sign ( value ) { let sign = NaN ; if ( _ . isNumber ( value ) ) { if ( value === 0 ) { sign = value ; } else if ( value >= 1 ) { sign = 1 ; } else if ( value <= - 1 ) { sign = - 1 ; } } return sign ; }
Returns a number representing the sign of `value`.

If `value` is a positive number, negative number, positive zero or negative zero,
the function will return 1, -1, 0 or -0 respectively. Otherwise, NaN is returned.

@static
@memberOf _
@category Math
@param {number} value A number
@returns {number} A number representing the sign
@example

_.sign(10);
// => 1

_.sign(-10);
// => -1
Returns a number representing the sign of value .