anaphora-anywhere --- anaphoric references without macros

The word "anaphoric" refers to the linguistic rule that a pronoun like "it" refers to the most recent object mentioned in a text. This simple library provides anaphoric references for Emacs Lisp in arbitrary contexts, not just certain macro calls, at the cost of making the binding reference explicit.

Anaphoric macros are familiar Lisp add-ons, popularized (if not invented) by Paul Graham in On Lisp, which bind a special variable (usually "it") to the last noted calculation. One disadvantage of these macros is that anaphoric reference may be made only to expressions at very specific points; moreover these points are introduced by a set of macros parallel to standard Lisp constructs. For example, in

(awhen (function-call arg1 arg2 arg3)
  (pp it))

the variable it is introduced by the awhen macro (that is, anaphoric when), and refers to the condition (function-call arg1 arg2 arg3).

This package introduces two functions for anaphoric reference.

• The its function tags a value to be referenced later, and returns its argument.

• The it function simply returns the last value memorized by its.

So under this library's approach, the example with macros above would be written

(when (its (function-call arg1 arg2 arg3))
  (pp (it)))

Instead of calling an anaphoric form of the when test, we mark the condition explicitly; instead of using the it variable, we make a call to the it function.

Indexed reference

Both its and it take an additional parameter which can be used to maintain differently indexed anaphoric reference. By default, the index is 0.