Static anonymous functions
Note
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Allow a 'static' modifier on lambdas and anonymous methods, which disallows capture of locals or instance state from containing scopes.
Avoid unintentionally capturing state from the enclosing context, which can result in unexpected retention of captured objects or unexpected additional allocations.
A lambda or anonymous method may have a static
modifier. The static
modifier indicates that the lambda or anonymous method is a static anonymous function.
A static anonymous function cannot capture state from the enclosing scope.
As a result, locals, parameters, and this
from the enclosing scope are not available within a static anonymous function.
A static anonymous function cannot reference instance members from an implicit or explicit this
or base
reference.
A static anonymous function may reference static
members from the enclosing scope.
A static anonymous function may reference constant
definitions from the enclosing scope.
nameof()
in a static anonymous function may reference locals, parameters, or this
or base
from the enclosing scope.
Accessibility rules for private
members in the enclosing scope are the same for static
and non-static
anonymous functions.
No guarantee is made as to whether a static anonymous function definition is emitted as a static
method in metadata. This is left up to the compiler implementation to optimize.
A non-static
local function or anonymous function can capture state from an enclosing static anonymous function but cannot capture state outside the enclosing static anonymous function.
Removing the static
modifier from an anonymous function in a valid program does not change the meaning of the program.
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