Data commit

Task/Range-expansion/Jsish/range-expansion.jsish

@@ -0,0 +1,40 @@
+#!/usr/bin/env jsish
+"use strict";
+
+/* Range expansion, in Jsish */
+function rangeExpand(rangeExpr) {
+
+    function getFactors(term) {
+        var matches = term.match(/(-?[0-9]+)-(-?[0-9]+)/);
+        if (!matches) return {first:Number(term)};
+        return {first:Number(matches[1]), last:Number(matches[2])};
+    }
+
+    function expandTerm(term) {
+        var factors = getFactors(term);
+        if (factors.length < 2) return [factors.first];
+        var range = [];
+        for (var n = factors.first; n <= factors.last;  n++) {
+            range.push(n);
+        }
+        return range;
+    }
+
+    var result = [];
+    var terms = rangeExpr.split(",");
+    for (var t in terms) {
+        result = result.concat(expandTerm(terms[t]));
+    }
+
+    return result;
+}
+
+if (Interp.conf('unitTest')) {
+;    rangeExpand('-6,-3--1,3-5,7-11,14,15,17-20');
+}
+
+/*
+=!EXPECTSTART!=
+rangeExpand('-6,-3--1,3-5,7-11,14,15,17-20') ==> [ -6, -3, -2, -1, 3, 4, 5, 7, 8, 9, 10, 11, 14, 15, 17, 18, 19, 20 ]
+=!EXPECTEND!=
+*/