* gash/arithmetic.scm: New file.
* Makefile.am (SOURCES): Add it.
* gash/lexer.scm (get-arithmetic-expansion): New procedure.
(get-expansion): Check for "$((" and use the new procedure to read an
arithmetic expansion.
* gash/eval.scm (word->qword): Handle '<sh-arithmetic>'.
* tests/unit/eval.scm: Add tests.
* tests/spec/Makefile.am (TESTS): Add 'arith'.
* tests/spec/oil.scm: Patch seven of its tests and filter out fifteen
others.
* doc/gash.texi, doc/syntax.txt: Add '<sh-arithmetic>' syntax.
* doc/gash.texi (Internal representation examples): In the section
on pipelines, change a redirect in the result to "ice-cream.txt" to
match its input.
* doc/gash.texi: Add an introduction, add a discussion of included and
missing features, document the parser interface, and remove the
indexes.
* doc/syntax.txt: Update to match the manual.
Timothy Sample
Stephen J. Scheck
Jan Nieuwenhuizen