Template/mixin ideas?

Chris Katko ckatko at gmail.com
Wed Oct 3 11:01:53 UTC 2018


I've got this simple task but I'm trying to perfect it as best I 
can to learn something in the process.

I have Linux terminal ASCII codes for coloring terminal output.

string red(string) { /* ... */ }

"Hello world".red => "\033[31mHello World\033[0m"

which translates to "[red]Hello World[reset to normal text]".

I have to do some slight trickery so I can chain them. But it all 
works fine. __The function is the same__ no matter what kind of 
color, bold, etc attribute I want. The only difference is the 
tag/prefix string.

So I have a table (or enum):
enum colors{
      reset = "\033[0m",
      red = "\033[31m",
      bold = "\033[1m" //...
      }

Absolute perfection would be some way to add a single line to 
that enum (or table) and magically get a new function. I add 
"blue" with its prefix code to the enum and immediately I can do:

"hello world".blue

Add yellow = "\033..." and I can do:

"hello world".bold.yellow

It's an interesting problem. Right now, I made a generic version 
that accepts the prefix code string directly called "color()" and 
red() translates to a call to color with the red string. blue() 
does the same. And so on. But it's still plenty of boiler plate. 
I do that so I don't have 80+ functions all a half-page 
long--which would be a nightmare to verify.

It's surely nothing mission critical. But I wonder if I can 
distill this simple problem down further, I may be able to learn 
some tricks for later problems.

Thanks.


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