Add colors and spaces when showing the method table

[andrioni]

Following František's suggestion in https://groups.google.com/forum/#!topic/julia-dev/_5zo8o8AogQ, I've made some changes to how methods and method tables are printed.

This is how it currently looks like on OS X with iTerm and its default colors:

Note: I've changed how parametric types are printed, but not tuples, since I tried to change the least amount of code used outside printing method tables possible.

[StefanKarpinski]

I actually think that the types are the most important part, so making everything else bold strikes me as contrary to what we actually want.

[andrioni]

Indeed, but maybe it would be better to use a different color in this case instead of bold.

I can't, however, decide which one is best. The list to choose from is black, red, green, yellow, blue, magenta, cyan and white.

[StefanKarpinski]

Also, keep in mind that we've had long discussions about what is and isn't visible on various people's screens, so while enabling this as an option is nice, there's a strong chance that it will be completely illegible on some people's systems, so we may not want it on by default.

[andrioni]

We could add more options to --color, something like no color, minimal colors and fully colored, but even then I still prefer to keep to the basic 16 colors, or even just the eight bold/bright variations.

[fhucho]

Yellow name with blue types looks best on my terminal but yellow will be invisible on light backgrounds... Couple of other options:

CL = "\e[0m"
BOLD = "\e[1m"
BLACK = "\e[30m"
RED = "\e[31m"
GREEN = "\e[32m"
YELLOW = "\e[33m"
BLUE = "\e[34m"
MAGENTA = "\e[35m"
CYAN = "\e[36m"
WHITE = "\e[37m"

function p(nm, tp)
    println("$(nm)sort$(CL)(r::$(tp)Range1{T<:Real}$(CL)) at range.jl:374")
    println("$(nm)sort$(CL)(v::$(tp)AbstractArray{T, 1}$(CL), d::$(tp)Integer$(CL), o::$(tp)Ordering$(CL), a::$(tp)Algorithm$(CL)) at deprecated.jl:19")
end

p("$YELLOW$BOLD", "$BOLD$BLUE")
p("$BLUE$BOLD", "$GREEN")
p("$BLUE$BOLD", "$BLUE")
p("$BLUE$BOLD", "$BLUE$BOLD")

[stevengj]

It would be nice to also have a writemime(io::IO, ::MIME"text/html", x::MethodTable) that used similar formatting in HTML, for display in IJulia (where terminal coloring codes won't work). See also #4952.

[andrioni]

Oh, I didn't know that worked! Should we use inline CSS or there is already a "default" custom stylesheet defined for IJulia?

Also, here's how it looks with yellow and blue:

[JeffBezanson]

Blue is very dark and hard to read in many terminals I've seen.

[ViralBShah]

Blue is unreadable on Windows.

[staticfloat]

It would be so neat if we could interrogate the system for the current color profile and choose intelligent colors based on that. I'm for this in principle, but as @StefanKarpinski points out, terminal colors can be difficult when you have such freedom for the user to set it up however they want. I'm still a little mad at my terminal for making git commit messages unreadable when the "black" foreground color is actually black.

[fhucho]

Bold or green types look quite readable and hopefully should look well on different terminals. To try it out paste this into the REPL:

CL = "\e[0m"
BOLD = "\e[1m"
BLACK = "\e[30m"
RED = "\e[31m"
GREEN = "\e[32m"
YELLOW = "\e[33m"
BLUE = "\e[34m"
MAGENTA = "\e[35m"
CYAN = "\e[36m"
WHITE = "\e[37m"

function p(nm, tp)
    println("$(nm)sort$(CL)(r::$(tp)Range1{T<:Real}$(CL)) at range.jl:374")
    println("$(nm)sort$(CL)(v::$(tp)AbstractArray{T, 1}$(CL), d::$(tp)Integer$(CL), o::$(tp)Ordering$(CL), a::$(tp)Algorithm$(CL)) at deprecated.jl:19")
end

p("", "$BOLD")
p("", "$GREEN")

[nalimilan]

Here on Linux with a white background the bold font is more visible than green.

Just an idea: should keyword arguments use a slightly different appearance to make the difference more visible than a small ; compared to ,?

[simonster]

It looks like readline is escaping the escape sequences when displaying the completion list for method(\t, at least in Konsole on Ubuntu 13.10:

julia> sort(\t
^[[1m^[[34msort^[[0m^[[1m(r::^[[0mRange1{T<:Real}^[[1m^[[1m) at range.jl:374
^[[1m^[[34msort^[[0m{T<:Real}^[[1m(r::^[[0mRange{T<:Real}^[[1m^[[1m) at range.jl:377
^[[1m^[[34msort^[[0m^[[1m(v::^[[0mAbstractArray{T, 1}^[[1m^[[1m) at sort.jl:321
^[[1m^[[34msort^[[0m^[[1m(v::^[[0mAbstractArray{T, 1}^[[1m, d::^[[0mInteger^[[1m, o::^[[0mOrdering^[[1m^[[1m) at deprecated.jl:19

[Keno]

Bump (just going through old issues :) )

[JeffBezanson]

I like the extra spaces but the color issue is too much of a bikeshed.

[hayd]

I had been running a similar patch for a while which made types more consistently cyan (IIRC julia currently uses cyan in some places for types). This made methods much easier to read.

If the issue is with black and white backgrounds perhaps there ought to be config options... julia already prints quite a few things in color so probably there is already an issue.

[garrison]

(FYI, to those watching this thread:) I created #11410, which puts spaces between function arguments but nowhere else.