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Readme.md

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+
+# Hash
+
+  C pointer hash.
+
+## Example
+
+```c
+hash_t *hash = hash_new();
+hash_set(hash, "name", "tobi");
+hash_set(hash, "species", "ferret");
+hash_set(hash, "age", "2");
+
+hash_each(hash, {
+  printf("%s: %s\n", key, (char *) val);
+});
+
+hash_free(hash);
+```
+
+yields:
+
+```
+species: ferret
+age: 2
+name: tobi
+```
+
+## API
+
+```c
+/*
+ * Hash type.
+ */
+
+typedef khash_t(ptr) hash_t;
+
+/*
+ * Allocate a new hash.
+ */
+
+#define hash_new() kh_init(ptr)
+
+/*
+ * Destroy the hash.
+ */
+
+#define hash_free(self) kh_destroy(ptr, self)
+
+/*
+ * Hash size.
+ */
+
+#define hash_size kh_size
+
+/*
+ * Iterate hash keys and ptrs, populating
+ * `key` and `val`.
+ */
+
+#define hash_each(self, block);
+
+/*
+ * Iterate hash keys, populating `key`.
+ */
+
+#define hash_each_key(self, block);
+
+/*
+ * Iterate hash ptrs, populating `val`.
+ */
+
+#define hash_each_val(self, block);
+
+// protos
+
+void
+hash_set(hash_t *self, char *key, void *val);
+
+void *
+hash_get(hash_t *self, char *key);
+
+int
+hash_has(hash_t *self, char *key);
+
+void
+hash_remove(hash_t *self, char *key);
+````