dist/joint.nowrap.js
function(length, opt) {

            if (!this.isDifferentiable()) return null;

            var t = this.tAtLength(length, opt);

            return this.tangentAtT(t);
        }
function(length, opt) {

            if (!this.isDifferentiable()) return null;

            var t = this.tAtLength(length, opt);

            return this.tangentAtT(t);
        }
function ( length , opt ) { if ( ! this . isDifferentiable ( ) ) return null ; var t = this . tAtLength ( length , opt ) ; return this . tangentAtT ( t ) ; }
Returns a tangent line at requested `length` with precision better than requested `opt.precision`; or using `opt.subdivisions` provided.
Returns a tangent line at requested length with precision better than requested opt . precision ; or using opt . subdivisions provided .