refactor based on overloading Base.show.

refactor_show_prototype.jl

@@ -0,0 +1,136 @@
+using Pkg
+Pkg.activate(@__DIR__)
+using Latexify
+import Base: show
+using SnoopCompile
+
+
+const Lmime = MIME"text/latexify"
+const lmime = MIME("text/latexify")
+
+const opdict = (;
+    :* => :Multiplication,
+    :/ => :Division,
+    :+ => :Addition,
+    :- => :Subtraction,
+    :^ => :Pow,
+)
+for T in values(opdict)
+    println(T)
+end
+abstract type AbstractLatexifyOperation end
+for T in values(opdict)
+    @eval(
+        struct $(T){S} <: AbstractLatexifyOperation
+            args::S
+        end
+    )
+end
+
+const ops = (; (keys(opdict) .=> eval.(values(opdict)))...)
+ops[:*]([:a, :b])
+
+for op in pairs(ops)
+    println(op[1], op[2])
+    @eval latexop(::Val{:call}, ::Val{$(QuoteNode(op[1]))}, args) = $(op[2])(args)
+end
+
+
+abstract type AbstractLatexifyEnvironment end
+for T in [:Align, :Equation, :Inline, :Bracket, :Raw, :Table]
+    @eval(
+        struct $(T){S} <: AbstractLatexifyEnvironment
+            args::S
+        end
+    )
+end
+Align(x, y) = Align(hcat(x, y))
+
+
+
+latexop(ex::Expr) = latexop(Val(ex.head), Val(ex.args[1]), ex.args[2:end])
+latexop(x) = x
+latexop(x...) = x
+latexop(x::Matrix) = Align(x)
+latexop(::Val{:align}, x) = Align(x)
+latexop(::Val{:equation}, x) = Equation(x)
+latexop(lhs::Vector, rhs::Vector) = Align(lhs, rhs)
+
+show(io::IO, ::MIME"text/latexify", x) = print(io, x)
+
+compare_precedence(a, b) = Base.operator_precedence(a) > Base.operator_precedence(b)
+function show(io::IO, mime::MIME"text/latexify", x::Multiplication)
+    surround = compare_precedence(get(io, :precedence, :+), :*)
+    io = IOContext(io, :precedence=>:*)
+    surround ? write(io, "\\left( ") : nothing
+    show(io, mime, x.args[1])
+    write(io, get(io, :multsign, " \\cdot "))
+    show(io, mime, x.args[2])
+    surround ? write(io, "\\right) ") : nothing
+end
+
+function show(io::IO, mime::MIME"text/latexify", x::Addition)
+    surround = compare_precedence(get(io, :precedence, :+), :+)
+    io = IOContext(io, :precedence=>:+)
+    surround ? write(io, "\\left(") : nothing
+    for arg in x.args[1:end-1]
+        show(io, mime, arg)
+        write(io, " + ")
+    end
+    show(io, mime, x.args[end])
+    surround ? write(io, "\\right)") : nothing
+end
+
+function show(io::IO, mime::MIME"text/latexify", x::Division)
+    write(io, "\\frac{")
+    show(io, mime, x.args[1])
+    write(io, "}{")
+    show(io, mime, x.args[2])
+    write(io, "}")
+end
+
+function show(io::IO, mime::MIME"text/latexify", x::Expr)
+    show(io, mime, latexop(x))
+end
+
+
+function join_matrix(io, m, delim = " & ", eol="\\\\\n")
+   nrows, ncols = size(m)
+   mime = MIME("text/latexify")
+   for (i, row) in enumerate(eachrow(m))
+       for x in row[1:end-1]
+            show(io, mime, x)
+            write(io, delim)
+       end
+       show(io, mime, row[end])
+       i != nrows && write(io, eol)
+    end
+    return nothing
+end
+
+
+function show(io::IO, mime::MIME"text/latexify", x::Align)
+    write(io, "\\begin{align}\n")
+    # join_show(io, x.args, " &= ")
+    join_matrix(io, x.args, " &= ")
+    write(io, "\n\\end{align}")
+end
+
+
+function _latex(args...; kwargs...)
+    io = IOBuffer(; append=true)
+    _latex(io, args...; kwargs...)
+    String(take!(io))
+end
+function _latex(io::IO, args...; kwargs...)
+    io = IOContext(io, kwargs...)
+    show(io, MIME("text/latexify"), latexop(args...))
+    return nothing
+end
+
+io = IOBuffer(; append=true)
+@time _latex(:(x/y))
+tinf = @snoopi_deep _latex(io, [1 2; :(x/y) 3])
+@time read(io, String) 
+using ProfileView
+ProfileView.view(flamegraph(tinf))