Re: ~_ is missing in CLISP

[Bruno Haible <haible@ilog.fr>]

Sam Steingold <sshteingold@cctrading.com> wrote:
> 
>      X3J13 vote 139 is not implemented (CLtL2 p 599)

Yes, format ~_ is not implemented, because it intermixes pretty printing
with `format'. But in my opinion, `prin1' (even with *print-pretty* = t)
is meant for producing machine-readable output, while `format' is made
for producing human-readable output. It is wrong to mix both.

For that matter, Guy L. Steele Jr. and Richard P. Gabriel wrote in their
article "The Evolution of Lisp":

 FORMAT is a mechanism for producing string output conveniently by, basically,
 taking a pre-determined string with placeholders and substituting computed
 values or strings for those placeholders -- though it became much more
 complex than this because the placeholders included iteration primitives for
 producing lists of results, plurals, and other such exotica. It may be
 loosely characterized as FORTRAN FORMAT statements gone berserk.

Bruno