Here's the modified code I used on hnacademic.com:

                         (let (typ id val view mod) it

    (def foo (...) 
        ...))
    ); unusual - last closing parens of a block on next line

Arc:

    arc> (def fn2() (def i() (prn "fn2-i")) (i))
    #<procedure: fn2>
    arc> (fn2)
    fn2-i
    "fn2-i"
    arc> (def fn1() (def i() (prn-"fn1-i")) (fn2) (i))
    #<procedure: fn1>
    arc> (fn1)
    *** redefining i
    *** redefining i
    fn2-i
    fn2-i
    "fn2-i"
    

    > (define (fn2) (define (i) (print "fn2-i")) (i))
    > (fn2)
       "fn2-i"> (define (fn1) (define (i) (print "fn1-i")) (fn2) (i)) 
    > (fn1)
       "fn2-i""fn1-i">

    (def Y2 (m) ((fn (f) (m (fn (a result) (f f) a result)))
          		(fn (f)	(m (fn (a result) (f f) a result)))))
    ; broken
    (def accumulate (combiner null-value term a next b)
    	((Y2 (fn (r)
    			(fn (a result)
    		   		(if (> a b) result
    		       		(r (next a) (combiner (term a) result))))))
    		a 
    		null-value))

For example, suppose I were to define a simple macro, nothing:

  (mac nothing () nil)

  (def doda (xs)
    (let nothing (table)
       (each x xs (assert (nothing x)))
       nothing ))

A better solution would be to try to ensure that only generally useful macros are added to arc.arc, and that they have names that are unlikely to be used as local variables. Or even better would be to make local variables shadow macros.

Consider this, though: "help" is defined as a macro. Some of the REPL-var code needs macros. The drop-into-scheme operator is a macro. I don't think we want to make people load a library file to use these.

    (require "lib/new-macros.arc")
    (new-macros)

    ($ % % %% %%% breakable defsop help make-br-fn or= redef)