Another lingering objection to arrows is this-binding (=> vs. ->).
*If* it is possible to make 'function'-free functions work, then how
about dropping the implicit bindings for 'arguments' and 'this' for
the short form? Then the 'function' keyword would be a modifier
on the short form, to re-introduce these implicit bindings.
That would support current code while connecting the semantic
difference (wrt 'this') to a more visible hint than -> vs =>.
This would still leave room for having both short functions and
block lambdas, as they serve different uses
function f(..) {..}
binds 'this', binds 'arguments', binds 'return'
f(..) {..}
no 'this', no 'arguments', binds 'return'
{|..| ..}
no 'this', no 'arguments', does not bind 'return'
(binding 'return' means that 'return' is local to this construct;
not binding 'return' means that 'return' is bound non-locally,
in a lexically enclosing construct).
There is at least one further dimension to this (abstracting
over expressions vs abstracting over statements), so there
may be room/need for another construct/modifier, to get
a more orthogonal design. It is part convenience, part
historical accident that Javascript has 'running a block'
mixed together with 'calling a callable'.
Claus
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