Values

Status: Stable

documented, exercised by the test suite and/or worked examples, with no known limitations recorded.

Description

Values[assoc]

Gives a list of the values of an association (or of a rule or list of rules).

Values[{assoc1, assoc2, ...}]

Threads over lists of associations and lists of rules.

Values[assoc, f]

Wraps each value: {f[v1], f[v2], ...}.

Examples (5)

Every input below was run against the current Mathilda build and its output recorded.

Basic examples (3)

In[1]:= Values[<|"a" -> 1, "b" -> 2|>]
Out[1]= {1, 2}

In[2]:= Values[<|"a" -> 1, "b" -> 2|>, f]
Out[2]= {f[1], f[2]}

In[3]:= Values[{<|"a" -> 1|>, {"b" -> 2}}]
Out[3]= {{1}, {2}}

Applications (2)

In[4]:= Values[<|a -> 1, b -> 2, c -> 3|>]
Out[4]= {1, 2, 3}

Wrap each value as f[v]

In[5]:= Values[<|a -> 1, b -> 2|>, f]
Out[5]= {f[1], f[2]}

Implementation notes

Algorithm. The base builtin_values (keys_or_values(res, want_keys=false)) walks the entries once and copies each rule's right-hand side into a fresh List, also accepting a single Rule or a bare list of rules. The extended forms come from the assoc_ops_init wrapper (ops_values → keys_values → kv_extract): Values[assoc, f] wraps each value as f[v], and both forms thread recursively over nested lists of associations and lists of rules.

Data structures. Plain Expr trees; one List of expr_copy'd values in insertion order. No hash index — it is a structural read.

Complexity / limits. O(n). A non-rule, non-association list element triggers Values::invrl (or leaves the call unevaluated inside an association).

Attributes: Protected.

References

See also: Keys

• Source: src/assoc.c
• Specification: docs/spec/builtins/data-structures.md
• Tests: tests/test_assoc_ops.c
• Tests: tests/test_association.c
• Tests: tests/test_compile_assoc.c
• Tests: tests/test_upvalues.c

Notes & additional examples

Notes

Values are returned in the association's insertion order, so Keys and Values line up positionally. Values[assoc, f] maps f over each value, and both forms thread over a list of associations or rules.