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docs/lib3x-hashmap_del.md

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+# hashmap_put
+
+This function deletes the mapping for the specified key from a [util/map/hashmap](https://openhome.cc/eGossip/OpenSCAD/lib3x-hashmap.html) if present. It returns a new map without the key/value.
+
+**Since:** 3.0
+
+## Parameters
+
+- `map` : The original map.
+- `key` : Adds the specified element to the specified set
+- `eq` : A equality function. If it's ignored, use `==` to compare elements.
+- `hash` : A hash function. If it's ignored, convert each element to a string and hash it. 
+
+## Examples
+
+    use <util/map/hashmap.scad>;
+    use <util/map/hashmap_get.scad>;
+    use <util/map/hashmap_del.scad>;
+
+    m1 = hashmap([["k1", 10], ["k2", 20], ["k3", 30]]);
+    m2 = hashmap_del(m1, "k1");
+    assert(hashmap_get(m2, "k1") == undef);