[Yaml-core] Quoted Streams

[Brian I. <briani@ActiveState.com>]

I was going to put this into my reply to Oren's block syntax proposal,
but I decided that's another issue altogether. BTW, I'm thinking that
one over too. I'll reply later today.

---

I want to propose yet another way of doing "streams" as we are now
calling them.

Last night, I had beers with Jeff Hobbs, a very bright guy from the Tcl
community (oxymoron? ;). We didn't get into *great* detail on YAML but
he had a strong suggestion on string syntax. It involved, wonder of
wonders, the double quote. 

My proposal is adapted from that discussion. The basic idea is that you
start every string with a double quote, and just keep going (regardless
of line breaks) until you hit the next (unescaped) double quote. Let's
try:

    a: "value"

I know. Bear with me.

    b: "Another value"
    c: "Another 
        value"

Semantically the same as c.

    d: "Another 
   value"

Boggle? But it works because whitespace is insignificant in streams. So
indentation is not enforced at all by the *parser*, only by the
*emitter*. And this is huge because:

    e: "Last night, I had beers with Jeff Hobbs, a very bright guy from
the Tcl community (oxymoron? ;). We didn't get into *great* detail on
YAML but he had a strong suggestion on string syntax. It involved,
wonder of wonders, the double quote."

I just cut and pasted the above paragraph into e. It parses fine! Now we
can dump huge pieces of text into YAML and (with a little escaping by
hand) just let the emitter clean things up for us.

    f:
        "Last night, I had beers with Jeff Hobbs, 
        a very bright guy from the Tcl community 
        (oxymoron? ;). We didn't get into *great* 
        detail on YAML but he had a strong 
        suggestion on string syntax. It involved, 
        wonder of wonders, the double quote."

This is how the value *might* get emitted.

Works fine in lists too (per Oren's new ideas on minimal lists):

    g: @
        "value"
        "Another
        value"
        "Works fine in lists too (per 
        Oren's new ideas on minimal 
                              lists):"

---

Obviously we can omit the quotes on simple values. I'll let Clark come
up with the escaping rules, etc.

BTW, I'm not even sure we *have* to escape double quotes, unless they
come at the end of a line. Just a thought.

Brian

-- 
perl -le 'use Inline C=>q{SV*JAxH(char*x){return newSVpvf
("Just Another %s Hacker",x);}};print JAxH+Perl'