var d3Shape = require("d3-shape");
data = [[0,0], [0.1, 0.5], [1,1]];
line = d3Shape.line(data); // make a line
console.log(line(data)); // output line
curve = d3Shape.curveBasis; // refererence curveBasis
line.curve(curve); // set the curve
console.log(line.curve()); // check
console.log(line(data)); // curve is not function ?
Created from: https://npm.runkit.com/d3-shape#line_context