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Macaulay2 > The Macaulay2 language > operators > .?

.? -- check for presence of elements whose key is a symbol

Description

x.?k -- the same as x#?(global k), tells whether a value is available with x.k.

See also

. -- access to elements whose key is a symbol
#? -- check for presence of elements

For the programmer

The object .? is a keyword.