Creates and returns a new hash table which, in addition to the standard functionality, can have a user-defined test, a user-defined hash function, and be a weak hash table.

make-hash-table &key *
test*
*
size*
*
rehash-size*
*
rehash-threshold*
*
hash-function*
*
weak-kind*
=> *
hash-table*

A designator for a function of two arguments, which returns ```
t
```

if they should be regarded as the same and ```
nil
```

otherwise.

A designator for a function of one argument, which returns a hash value.

One of ```
:value
```

, ```
t
```

, ```
:key
```

, ```
:both
```

, ```
:one
```

, ```
:either
```

, ```
nil
```

. The default is ```
nil
```

.

The standard definition of ```
make-hash-table
```

is extended such that *
test*
can be any suitable user-defined function. If *
test*
is not one of the standard test functions (```
eq
```

, ```
eql
```

, ```
equal
```

and ```
equalp
```

), and if *
hash-function*
is not supplied, then the hash value is the same as would be used if *
test*
were ```
equalp
```

.

*
hash-function*
may be supplied only if *
test*
is not one of the standard test functions. It takes a hash key as its argument and returns a hash value to use for hashing.

If *
weak-kind*
is non-```
nil
```

, it makes *
hash-table*
weak. Its semantics are the same as the second argument of set-hash-table-weak, that is:

```
(make-hash-table :weak-kind
```*
weak-kind <other-args>*
)

(let ((ht (make-hash-table<other-args>)))

(set-hash-table-weak htweak-kind)

ht)

LispWorks Reference Manual - 6 Apr 2005