A user submits text to your program with an input field. In Javascript, this is always a string.
But sometimes you need a number:
R.pipe(
parseInt,
R.defaultTo(0)
)("650"); // output: 650
This converts the input (string) to a number. If the input is undefined, null
or NaN
, it returns the argument to Ramda’s defaultTo
(in this case 0).
R.pipe(
parseInt,
R.defaultTo(0)
)(""); // output: 0