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Function
src/index.ts:1022nerdamer.contains
nerdamer.contains(x: Expression | Vector | ValuesSet | Dictionary | SolutionSet, value: ExpressionInput): ExpressionTests whether a value is present in a supported finite container.
remarks
Vector membership uses the vector's element equality, while ValuesSet and
SolutionSet delegate to their semantic set membership. Dictionary membership checks
keys rather than stored values. Unsupported container types remain symbolic.
Parameters
| Name | Type | Description |
|---|---|---|
x | Expression | Vector | ValuesSet | Dictionary | SolutionSet | Vector, finite set, solution set, or dictionary to search. |
value | ExpressionInput | Value to look up, or dictionary key when x is a Dictionary. |
Returns
Expression — 1 when the value is found and 0 otherwise.
Examples
const d = Parser.parse('{x=>1, y=>a}') as Dictionary;
contains(d, 'x').text(); // 1
const v = new Vector(['x', 1, 2]);
contains(v, 10).text(); // 0