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docs/lib3x-hashmap_put.md

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+# hashmap_put
+
+This function returns the length of a [util/map/hashmap](https://openhome.cc/eGossip/OpenSCAD/lib3x-hashmap.html).
+
+**Since:** 3.0
+
+## Parameters
+
+- `map` : The original map.
+
+## Examples
+
+    use <util/map/hashmap.scad>;
+    use <util/map/hashmap_put.scad>;
+    use <util/map/hashmap_get.scad>;
+
+    m1 = hashmap([["k1", 10], ["k2", 20], ["k3", 30]]);
+
+    m2 = hashmap_put(m1, "k4", 40);
+    assert(hashmap_get(m2, "k4") == 40);