r-lib
Guidance colorizing values within a column
I'm excited about this package, and am hopeful it might fit my needs.
I'm trying to colorize values within a column - I have logic, functions, methods I can use to colorize values in a column. I do not see how to apply this logic.
The simplest use case is to colorize positive numeric values blue, since negative is red.
Similarly, I have categorical colors, how might I apply them to a character column?
Best guess, I need to write custom functions to override pillar:::pillar_shaft.classname() for every column class, by the class of data in each column.
Is there another way to inject color into the output?
The vignette/extensions does not describe where to inject color. The custom Body function does receive column values, however they are pillar_component objects which contain data values in the form of (undocumented) pillar_ornament object. I think these values have already been updated by a previous pillar_shaft() step.
In the vctrs package, the vignette "Printing vectors nicely in tibbles" implements a custom function deg_min_color() to demonstrate how to colorize parts of column values. This mechanism is applied to all columns of a given class. So it leads me to conclude that I need to write custom functions for each column class.
However, if I implement a custom pillar_shaft.numeric(), it misses all the fun stuff that happens inside the (hidden) pillar:::pillar_shaft_number(). Same for pillar:::pillar_shaft.character().
Finally, I see new_pillar_shaft() can accept ANSI escape codes in argument formatted, however I don't see how to provide ANSI formatting of my own.
Ideal world, I'd like to pass an optional colorization function... somewhere. :)
Thank you for any guidance!
I'll be upfront, I anticipate a totally reasonable response might be "Try it and let us know if it works."
I think that's a reasonable next step, no shade.
Imagine I write custom functions pillar_shaft.numeric(), pillar_shaft.integer64(), pillar_shaft.character(), pillar_shaft.factor() I probably cover everything I could reasonable handle. If it doesn't work for some reason, then I have something concrete to post and ask.
However, if there happens to be an easier mechanism that I'm missing, then let me know if you have a few minutes. :) Or let me know there is one and I'll look harder for it. Best to you.
Thanks for your interest.
I can't spend time thinking deeply about it now. Have you seen https://pillar.r-lib.org/articles/printing.html?
If that doesn't help, a good way might be to implement your desired behavior in a fork of the pillar package. We could then think about how to implement this using the existing extension options.
