1 | var _arity =
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2 | /*#__PURE__*/
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3 | require("./internal/_arity");
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4 |
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5 | var _curry1 =
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6 | /*#__PURE__*/
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7 | require("./internal/_curry1");
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8 |
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9 | var map =
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10 | /*#__PURE__*/
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11 | require("./map");
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12 |
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13 | var max =
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14 | /*#__PURE__*/
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15 | require("./max");
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16 |
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17 | var reduce =
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18 | /*#__PURE__*/
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19 | require("./reduce");
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20 | /**
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21 | * Returns a function, `fn`, which encapsulates `if/else, if/else, ...` logic.
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22 | * `R.cond` takes a list of [predicate, transformer] pairs. All of the arguments
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23 | * to `fn` are applied to each of the predicates in turn until one returns a
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24 | * "truthy" value, at which point `fn` returns the result of applying its
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25 | * arguments to the corresponding transformer. If none of the predicates
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26 | * matches, `fn` returns undefined.
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27 | *
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28 | * @func
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29 | * @memberOf R
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30 | * @since v0.6.0
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31 | * @category Logic
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32 | * @sig [[(*... -> Boolean),(*... -> *)]] -> (*... -> *)
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33 | * @param {Array} pairs A list of [predicate, transformer]
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34 | * @return {Function}
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35 | * @see R.ifElse, R.unless, R.when
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36 | * @example
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37 | *
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38 | * const fn = R.cond([
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39 | * [R.equals(0), R.always('water freezes at 0°C')],
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40 | * [R.equals(100), R.always('water boils at 100°C')],
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41 | * [R.T, temp => 'nothing special happens at ' + temp + '°C']
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42 | * ]);
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43 | * fn(0); //=> 'water freezes at 0°C'
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44 | * fn(50); //=> 'nothing special happens at 50°C'
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45 | * fn(100); //=> 'water boils at 100°C'
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46 | */
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47 |
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48 |
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49 | var cond =
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50 | /*#__PURE__*/
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51 | _curry1(function cond(pairs) {
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52 | var arity = reduce(max, 0, map(function (pair) {
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53 | return pair[0].length;
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54 | }, pairs));
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55 | return _arity(arity, function () {
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56 | var idx = 0;
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57 |
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58 | while (idx < pairs.length) {
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59 | if (pairs[idx][0].apply(this, arguments)) {
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60 | return pairs[idx][1].apply(this, arguments);
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61 | }
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62 |
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63 | idx += 1;
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64 | }
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65 | });
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66 | });
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67 |
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68 | module.exports = cond; |
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