Remove the initial empty string from quasi-literals, if possible.

Remove the initial empty string from quasi-literals, if possible.

`${x} + ${y}` ==> (x + " + " + y)
`${x}${y}++`  ==> ("" + x + y + "++")

"Default template string can be simplified"
BUG=http://code.google.com/p/traceur-compiler/issues/detail?id=133

[usrbincc, 2012-10-17 18:04:06]

For convenience:

#--cut--
build/build
cat > quasi-133.js <<END
`${x} + ${y}`;  // (x + " + " + y);
` ${x} + ${y}`; // (" " + x + " + " + y);
`${x}${y}++`;   // ("" + x + y + "++");
END
./traceurc quasi-133.js
cat out/quasi-133.compiled.js
#--cut--

[arv, 2012-10-17 18:55:10]

I think this one can use some more tests.

var x = 1, y = 2, z = 3;
assertEquals('1', `${x}`);
assertEquals('123', `${x}${y}`);
assertEquals('1 2', `${x} ${y}`);
assertEquals(' 12', ` ${x}${y}`);
assertEquals('12 ', `${x}${y} `);

This one should include bin/traceur.js since it uses quasis

https://codereview.appspot.com/6711049/diff/2001/src/codegeneration/QuasiLite...
File src/codegeneration/QuasiLiteralTransformer.js (right):

https://codereview.appspot.com/6711049/diff/2001/src/codegeneration/QuasiLite...
src/codegeneration/QuasiLiteralTransformer.js:283: if(element.value.value ===
'')
if (

https://codereview.appspot.com/6711049/diff/2001/src/codegeneration/QuasiLite...
src/codegeneration/QuasiLiteralTransformer.js:285: else if(firstNonEmpty < 0 &&
i === 2)
else if (

[arv, 2012-10-17 19:08:14]

I forgot to say that this is awesome. I didn't realize we could also
remove inner "" like your patch does.

On Wed, Oct 17, 2012 at 2:55 PM,  <arv@chromium.org> wrote:
> I think this one can use some more tests.
>
> var x = 1, y = 2, z = 3;
> assertEquals('1', `${x}`);
> assertEquals('123', `${x}${y}`);
> assertEquals('1 2', `${x} ${y}`);
> assertEquals(' 12', ` ${x}${y}`);
> assertEquals('12 ', `${x}${y} `);
>
> This one should include bin/traceur.js since it uses quasis
>
>
>
https://codereview.appspot.com/6711049/diff/2001/src/codegeneration/QuasiLite...
> File src/codegeneration/QuasiLiteralTransformer.js (right):
>
>
https://codereview.appspot.com/6711049/diff/2001/src/codegeneration/QuasiLite...
> src/codegeneration/QuasiLiteralTransformer.js:283:
> if(element.value.value === '')
> if (
>
>
https://codereview.appspot.com/6711049/diff/2001/src/codegeneration/QuasiLite...
> src/codegeneration/QuasiLiteralTransformer.js:285: else if(firstNonEmpty
>
> < 0 && i === 2)
> else if (
>
> https://codereview.appspot.com/6711049/



-- 
erik

[slightlylate, 2012-10-18 10:53:50]

Love this. Would love to approve this once it's rebased and the nits are fixed.

[usrbincc, 2012-10-22 18:38:30]

Sorry for taking so long to pop the stack to this point.

I can't take credit for optimizing out the inner "", since that was
already in the code. Just the leading one.

[arv, 2012-10-22 20:24:09]

LGTM

Committed as

https://code.google.com/p/traceur-compiler/source/detail?r=0bd9f5b84e99cd3163...