`infix` consistency (update.kt)

[Jolanrensen]

Currently, we can write something like:

dfGrouped
    .update { something }
    .where { it.director == null } asFrame {
        update { director } with { "None" }
}

However, it seems a bit random as to which functions are infix and which aren't.
We need to either make everything infix or limit infix to just "inside" DSLs, like add.
Currently infix: Update.withValue, Update.perRowCol, Update.with, Update.asFrame, GroupClause.into. Might also want to check other files to be sure.

[Jolanrensen]

It doesn't look thát wrong:

val dfGrouped = df group { title and director } into something

dfGrouped update {
    something
} where {
    it.director == null
} asFrame {
    update { director } withValue "None"
}

or

val dfGrouped = df group { title and director } into something

dfGrouped update { something } where { it.director == null } asFrame {
    update { director } withValue "None"
}

But know that vararg doesn't work, so df update("something") would suddenly need a period.

[nikitinas]

I suggest to keep infix for terminal operations (e.g. into or with) and remove for others.

[Jolanrensen]

@nikitinas why for those? Any design philosophy behind it? In the docs or examples, it's not used as far as I can see.

[nikitinas]

I thought it would be consistent with infix nature of into in column selectors and groupBy aggregations... But actually it's quite different from chaining several calls as in df.group { columns }.into("group").

So, let's remove all top-level infix functions.