The capture-list is a comma-separated list of zero or more captures, optionally beginning with the capture-default. The only capture defaults are & (implicitly catch the odr-used automatic variables and *this by reference) and = (implicitly catch the odr-used automatic variables by copy and implicitly catch *this by reference if it is odr-used).
this захватывается по ссылке.
[this] captures the this pointer by value
в словаре нельзя так хранить вызов функции ?