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1var _arity =
2/*#__PURE__*/
3require("./internal/_arity");
4
5var _concat =
6/*#__PURE__*/
7require("./internal/_concat");
8
9var _curry2 =
10/*#__PURE__*/
11require("./internal/_curry2");
12/**
13 * `tryCatch` takes two functions, a `tryer` and a `catcher`. The returned
14 * function evaluates the `tryer`; if it does not throw, it simply returns the
15 * result. If the `tryer` *does* throw, the returned function evaluates the
16 * `catcher` function and returns its result. Note that for effective
17 * composition with this function, both the `tryer` and `catcher` functions
18 * must return the same type of results.
19 *
20 * @func
21 * @memberOf R
22 * @since v0.20.0
23 * @category Function
24 * @sig (...x -> a) -> ((e, ...x) -> a) -> (...x -> a)
25 * @param {Function} tryer The function that may throw.
26 * @param {Function} catcher The function that will be evaluated if `tryer` throws.
27 * @return {Function} A new function that will catch exceptions and send then to the catcher.
28 * @example
29 *
30 * R.tryCatch(R.prop('x'), R.F)({x: true}); //=> true
31 * R.tryCatch(() => { throw 'foo'}, R.always('catched'))('bar') // => 'catched'
32 * R.tryCatch(R.times(R.identity), R.always([]))('s') // => []
33 * R.tryCatch(() => { throw 'this is not a valid value'}, (err, value)=>({error : err, value }))('bar') // => {'error': 'this is not a valid value', 'value': 'bar'}
34 */
35
36
37var tryCatch =
38/*#__PURE__*/
39_curry2(function _tryCatch(tryer, catcher) {
40 return _arity(tryer.length, function () {
41 try {
42 return tryer.apply(this, arguments);
43 } catch (e) {
44 return catcher.apply(this, _concat([e], arguments));
45 }
46 });
47});
48
49module.exports = tryCatch;
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