Proposal: warning or error when using an undefined variable

[andrewrk]

a = 3
b = a + c

expected output:

SyntaxError: reading from undefined "c" on line 2

[andrewrk]

Potential issues: using the window or require object.

Possible solutions:

• whitelist these variables
• accept a command line argument with whitelisted variables
• have a predefined set of whitelisted variables in a "node" category and a "browser" category and have a way to select the target output
• have a config file that coco will look up the directory tree for with the predefined variables listed in them, similar to .jshintrc
• a way to mark globals in coco source

[satyr]

Whitelisting is the hardest part. Can't you simply use JSHint?

[andrewrk]

Can't you simply use JSHint?

Problems:

• that's a 2 step process instead of 1. For example, that would ruin the syntastic experience.
• coco output isn't suited for jshint
• jshint errors are about the generated source, not the coco source.