HashDispatcher

(class from pyomo.common.collections._hasher)

class pyomo.common.collections._hasher.HashDispatcher(*args, **kwargs)

Bases: defaultdict

Dispatch table for generating “universal” hashing of all Python objects.

This class manages a dispatch table for providing hash functions for all Python types. When an object is passed to the Hasher, it determines the appropriate hashing strategy based on the object’s type:

• If a custom hashing function is registered for the type, it is used.

• If the object is natively hashable, the default hash is used.

• If the object is unhashable, the object’s id() is used as a fallback.

The Hasher also includes special handling for tuples by recursively applying the appropriate hashing strategy to each element within the tuple.

__init__(*args, **kwargs)

Methods

__init__(*args, **kwargs)
clear()	Remove all items from the dict.
copy()
fromkeys(iterable[, value])	Create a new dictionary with keys from iterable and values set to value.
get(key[, default])	Return the value for key if key is in the dictionary, else default.
hashable(obj[, hashable])
items()	Return a set-like object providing a view on the dict's items.
keys()	Return a set-like object providing a view on the dict's keys.
pop(k[,d])	If the key is not found, return the default if given; otherwise, raise a KeyError.
popitem()	Remove and return a (key, value) pair as a 2-tuple.
setdefault(key[, default])	Insert key with a value of default if key is not in the dictionary.
update([E, ]**F)	If E is present and has a .keys() method, then does: for k in E.keys(): D[k] = E[k] If E is present and lacks a .keys() method, then does: for k, v in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k]
values()	Return an object providing a view on the dict's values.

Attributes

default_factory

Factory for default value called by __missing__().

Member Documentation

clear()

Remove all items from the dict.

copy() → a shallow copy of D.

classmethod fromkeys(iterable, value=None, /)

Create a new dictionary with keys from iterable and values set to value.

get(key, default=None, /)

Return the value for key if key is in the dictionary, else default.

items()

Return a set-like object providing a view on the dict’s items.

keys()

Return a set-like object providing a view on the dict’s keys.

pop(k[, d]) → v, remove specified key and return the corresponding value.

If the key is not found, return the default if given; otherwise, raise a KeyError.

popitem()

Remove and return a (key, value) pair as a 2-tuple.

Pairs are returned in LIFO (last-in, first-out) order. Raises KeyError if the dict is empty.

setdefault(key, default=None, /)

Insert key with a value of default if key is not in the dictionary.

Return the value for key if key is in the dictionary, else default.

update([E, ]**F) → None.  Update D from mapping/iterable E and F.

If E is present and has a .keys() method, then does: for k in E.keys(): D[k] = E[k] If E is present and lacks a .keys() method, then does: for k, v in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k]

values()

Return an object providing a view on the dict’s values.

default_factory

Factory for default value called by __missing__().