How to change default in <>> method on NodeProxy

Questions
1

(From NodeProxy’s Help page)

<<>(proxy, key: ‘in’)
Chaining. Usage: proxyA <<> proxyB <<> proxyC <<> … . Map proxyC source to proxyB \in argument, and proxyB to proxyA’s in argument.

It seems to say in the documentation that you can change the default mapping from ‘in’ to some other key, for example ‘foo’, but my attempts to do this have met with syntactic errors. What is the right way to do this?

2 
a <>>.foo b

Syntactically, this is an adverb: Adverbs for Binary Operators | SuperCollider 3.12.2 Help – there are some standard adverbs defined for math operators, but the adverb itself is just a symbol attached to the operator. <>> and <<> use this symbol for an argument name.

hjh

3

That does work. It seems like the Help documentation is opaque on this one. Thanks.