Initial data commit

Task/Filter/Nim/filter.nim

@@ -0,0 +1,19 @@
+import sequtils
+
+let values = toSeq(0..9)
+
+# Filtering by returning a new sequence.
+# - using an explicit filtering procedure.
+echo "Even values: ", values.filter(proc(x: int): bool = x mod 2 == 0)
+# - using a predicate.
+echo "Odd values: ", values.filterIt(it mod 2 == 1)
+
+# Filtering by modifying the sequence.
+# - using an explicit filtering procedure.
+var v1 = toSeq(0..9)
+v1.keepIf(proc(x: int): bool = x mod 2 == 0)
+echo "Even values: ", v1
+# - using a predicate.
+var v2 = toSeq(0..9)
+v2.keepItIf(it mod 2 != 0)
+echo "Odd values: ", v2