Comment by antocuni

hello, spy author here.

> Why do blue functions disappear when redshifting? If you red shift blue then it goes down in frequency so you might get green or red. Perhaps my physics brain is just over thinking it!

yes I think you are overthinking :). It's not meant to be accurate physics of course.

The usage of colors to distinguish comptime vs runtim code comes from PyPy: in that context, we used "green" and "red", and initial versions of SPy used the same convention.

Then someone pointed out that green/red is not colorblind friendly and so I changed it to blue.

Having actual colors for the two phases is VERY useful for visualization: e.g. we already have a "spy --colorize" command which shows you which parts are blue and which are red.

As for "redshifting": the AST "before" has a mixture of blue and red colors, while the AST "after" has only red nodes, thus the final AST is "more red" than the first one, that's why I chose that name.