path_expansion

Variable/path expansion and quoting.

This is just working and I haven't given it much thought yet. I don't know if this is good or bad. or if I shouldn't just make an entire macro system after lisp.

I created this, because, I think, in the process of adding variable bindings I broke the old fashioned do-list. But I don't remember. It's been a tough summer with the concussion and cataractes and all.

Either way, here it is. ~ causes the thing after to be expanded to it's value if it can be resolved.

If the thing starts with:

• / it's taken to be an absolute path in the datastore.
• . it's taken to be a value in the current with.
• Otherwise it's taken to be a value in the current with stack.

A back ` protects something from being expanded once. This allows for the function being defined to be a reference to be expanded at execution time, instead of being expanded at definition time.

without the ` the function could still work but would be the equivalent of a hard coded value. Strings are weird here.

At any rate, here's an example session. It's the default with stack of /home with msg in it. So msg can be found three ways from the standpoint of expansion..

• ~/home/msg - goes directly to there
• ~.msg - looks for it in the top with, (/home).
• ~msg - looks for it in the entire with-stack.

Another affect of '.' is with pop. When popping results which are maps if popping to '.' the map will be merged into the current with.

SPR:> with /home

msg                           

SPR:> with-stack /home /

SPR:> show /home msg: hello, welcome home.

SPR:> def foo "myfoo" log/info `~.msg

SPR:> help foo

SPR Help

foo

"myfoo" Type: dolist Source: [log/info ~.msg]

SPR:> def foo "myfoo" log/info `~msg

SPR:> help foo

SPR Help

foo

"myfoo" Type: dolist Source: [log/info ~msg]

SPR:> foo hello, welcome home.

SPR:> def foo "myfoo" log/info `~.msg

SPR:> foo hello, welcome home.

SPR:> def foo "myfoo" log/info `~/home/msg

SPR:> foo hello, welcome home.

SPR:> show /home msg: hello, welcome home.

SPR:> def foo "myfoo" log/info `~/home/msg

SPR:> foo hello, welcome home.

SPR:> help foo

SPR Help

foo

"myfoo" Type: dolist Source: [log/info ~/home/msg]

SPR:> def foo "myfoo" log/info `~.msg

SPR:> help foo

SPR Help

foo

"myfoo" Type: dolist Source: [log/info ~.msg]

SPR:> foo hello, welcome home.

SPR:> def foo "myfoo" log/info `~msg

SPR:> foo hello, welcome home.