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Template std.functional.unaryFun

Transforms a string representing an expression into a unary function. The string must either use symbol name a as the parameter or provide the symbol via the parmName argument.

template unaryFun(alias fun, string parmName = "a") ;

Contained Functions



fun a string or a callable
parmName the name of the parameter if fun is a string. Defaults to "a".


If fun is a string, a new single parameter function

If fun is not a string, an alias to fun.


// Strings are compiled into functions:
alias isEven = unaryFun!("(a & 1) == 0");
assert(isEven(2) && !isEven(1));


Andrei Alexandrescu


Boost License 1.0.