About the element-wise operation

[tztsai]

In Julia, element-wise operations can be realized by the dot symbol ".". However, for arithmetic operations like "+", "-", "*", "/", etc., the dot is put before the operation symbol, e.g. ".+", ".-", while for functions the dot is put after the function name. Since these operation symbols are also generic functions in Julia (we can write +(1, 2) as an equivalent of 1+2), would it be more consistent if the dot is put after the function for both symbolic operations and named functions? For example, 1+.x instead of 1 .+ x.

[dkarrasch]

That inconsistency seems to only affect operators for which there is an in-fix notation available. When using pre-fix notation, the same rule applies as for every other function:

julia> x = (1,2)
(1, 2)

julia> (+).(1, x)
(2, 3)

Since in-fix notation is special ("inconsistent") compared to the usual function notation, I'd argue that the inconsistency about the broadcasting dot is consistent. 😄

[fredrikekre]

xref #8450, #20249 (comment), #20540

[StefanKarpinski]

The other way to look at this is that in f.(x) the dot is in front of the ( just as it is in front of the + in a .+ b.