aesthetics of variable references and function calls

[Robert P. J. Day]

  a picky point, but i've been curious about this feature and reading the 
first part of chapter 8, i finally decided to ask about it.

  i've noticed the alternative ways to refer to variables and function 
calls:

  $(whatever)
  ${whatever}

and, strictly for aesthetics, i standardized on using ${} for variable 
references and $() for function calls, just given the historic precedent 
set by the corresponding shell features.  obviously, it's a matter of 
personal taste, but i was curious about the advice in chapter 8:

"If the arguments themselves contain other function calls or variable 
references, it is wisest to use the same kind of delimiters for all the 
references; write `$(subst a,b,$(x))', not `$(subst a,b,${x})'. This is 
because it is clearer, and because only one type of delimiter is matched 
to find the end of the reference."

personally, given my standards, i'd use the second form, even if it meant
mixing and matching delimiters.  i'm curious about what other folks use, 
whether they care one way or the other, and if there are some make 
"programming standards" that go beyond just "here's how make works."

i'm already perusing www.paulandlesley.org -- any other good sources for 
make programming standards?  thanks.

rday

p.s.  would using mixed delimiters possibly identify syntax errors sooner 
in the parsing process, if the delimiters don't match exactly?