Katex hyper fun

katex_hyper_fun.jl

### A Pluto.jl notebook ###
# v0.15.0

using Markdown
using InteractiveUtils

# This Pluto notebook uses @bind for interactivity. When running this notebook outside of Pluto, the following 'mock version' of @bind gives bound variables a default value (instead of an error).
macro bind(def, element)
    quote
        local el = $(esc(element))
        global $(esc(def)) = Core.applicable(Base.get, el) ? Base.get(el) : missing
        el
    end
end

# ╔═╡ c7fd078d-862f-42a2-a515-221ed411b4fb
using PlutoUI

# ╔═╡ 899f5d16-7018-4297-9939-0a4b5eb30620
using HypertextLiteral

# ╔═╡ 1a6943bf-ede7-4690-80de-e9ec23cc66da
katex_base_code = @htl("""
		<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.13.11/dist/katex.min.css" integrity="sha384-Um5gpz1odJg5Z4HAmzPtgZKdTBHZdw8S29IecapCSB31ligYPhHQZMIlWLYQGVoc" crossorigin="anonymous">
			<style>
			.katex .base, 
			.katex .strut {
				/*display: inline-flex !important;*/
				pointer-events: none;
			}
			.SlottedLaTeX {
				font-size: .75em;
			}
			.SlottedLaTeX .slot {
				pointer-events: initial;
			}
			</style>
		<script src="https://cdn.jsdelivr.net/npm/katex@0.13.11/dist/katex.min.js" integrity="sha384-YNHdsYkH6gMx9y3mRkmcJ2mFUjTd0qNQQvY9VYZgQd7DcN7env35GzlmFaZ23JGp" crossorigin="anonymous"></script>
""")

# ╔═╡ b0ce1300-df3c-11eb-30ca-e7fee566afae
begin
	Base.@kwdef struct SlottedLaTeX
		parts::Vector{String}
		slots::Vector{Any}
		defined_commands::Vector=[]
		used_commands::Vector=[]
		used_commands_defs::Vector=[]
	end
	
	function Base.show(io::IO, m::MIME"text/html", sl::SlottedLaTeX)
		defined_command_names = map(c -> c[1], sl.defined_commands)

		
		commands_defs = join(map(comm -> "\\newcommand\\$(comm[1])$(comm[2])\n",
				filter(x -> x[1] ∉ defined_command_names, collect(zip(sl.used_commands, sl.used_commands_defs)))
			))
		parts = map(part -> "$commands_defs $part", sl.parts)
		h = @htl("""
			$katex_base_code
			
			<span class="SlottedLaTeX-slots" style="display: none;">
			$(
				map(sl.slots) do s
					@htl("<span class='slot'>$(s)</span>")
				end
			)
			</span>
			<script>
			// https://unicode-table.com/en/#2800
			const braille_start = 10240
			// https://unicode-table.com/en/#03B1
			const greek_start = 945
			const placeholder = (i) => String.fromCodePoint(braille_start + i)
			const placeholder_index = (s) => s.codePointAt(0) - braille_start
			const k = (segments, ...slots) => {
				const mock = [...slots.flatMap((_, i) => [segments[i], placeholder(i)]), segments[segments.length-1]].join("")
				const el = html`<span class='SlottedLaTeX'></span>`
				katex.render(mock, el, {
					displayMode: currentScript.closest("p") == null,
				})
				Array.from(el.querySelectorAll("span")).forEach(span => {
					const t = span.innerText
					if(t.length === 1) {
						const i = placeholder_index(t)
						if(0 <= i && i < slots.length) {
							span.replaceWith(slots[i])
						}
					}
				})
				return el
			}
			const parts = $(parts)
			console.log(parts)
			const slots = Array.from(currentScript.previousElementSibling.children)
			console.log(slots)
			return k(parts, ...slots)
			</script>
		""")

		Base.show(io, m, h)
	end
end

# ╔═╡ aab42b5e-3d81-454f-97c7-e39bbb0ba425
begin
latex_name(s) = Symbol("__LATEX_$s")
latex_name(vec::Vector) = latex_name(vec[1])
end

# ╔═╡ 3edb1f40-3cb0-4ef9-a917-047fbdfc7c33
begin
	tex(s::String) = tex(Expr(:string, s)) #SlottedLaTeX(parts=[s], slots=[])
	function tex(ex::Expr)
		@assert ex.head === :string "$(ex.head)"
		if ex.args[1] isa String
			parts = String[ex.args[1]]
			slots = Any[]
		else
			parts = ["\\hspace{0pt}"]
			slots = [ex.args[1]]
		end
		for x in ex.args[2:end]
			if x isa String			
				all(==(' '), x) ? push!(parts, "\\hspace{0pt}") : push!(parts, x)
			else
				length(parts) != length(slots) + 1 && push!(parts, "\\hspace{0pt}")
				push!(slots, x)
			end
		end
		if length(slots) == length(parts)
			push!(parts, "\\hspace{0pt}")
		end

		used_commands = collect(Iterators.flatten(map(parts) do part
			matches = eachmatch(r"\\([a-zA-Z]+)", part)
			map(match -> match.captures, matches)
		end))

		defined_commands = collect(Iterators.flatten(map(parts) do part
			matches = eachmatch(r"\\newcommand\\([a-zA-Z]+)(.+)\n", part)
			map(match -> match.captures, matches)
		end))

		defined_exprs = map(defined_commands) do command
			Expr(:(=), esc(latex_name(command[1])), command[2])
		end
		
		usage_name_symbols = filter(name -> isdefined(@__MODULE__, name[2]), map(x -> (x[1], latex_name(x[1])), used_commands))
		symbols = map(x -> x[2], usage_name_symbols)
		names = map(x -> x[1], usage_name_symbols)
		
		quote
			$(defined_exprs...)
			commands = [$(symbols...)]
			SlottedLaTeX(
				parts = $parts,
				slots = [$(esc.(slots)...)],
				defined_commands=$defined_commands,
				used_commands=$names,
				used_commands_defs=commands,
				
			)
		end
	end
end

# ╔═╡ 4d007aa4-831f-4933-a96d-38e9ed3e8d46
macro tex_str(s)
	ex = Meta.parse("\"" * s * "\"")
	tex(ex)
end

# ╔═╡ 3bbc1d6d-86c6-4ad8-b8a8-e2154bd11352
macro tex(exp)
	:(tex($exp))
end

# ╔═╡ bc8a2c67-f944-4999-87c9-1cc17467cbe8
jjj = tex"""
\\newcommand\\Par[1]{{ \\left( {#1} \\right] }}

\\frac {xxx}{\\Par{N} + $(@bind x Scrubbable(10))}
"""

# ╔═╡ c7581a61-f600-40f1-960f-127e9de2c2e8
jjj

# ╔═╡ acaa17f6-9e56-4ed1-8545-ea2f0653f3b7
tex"""
\\frac 1{\\Par{N}}
"""

# ╔═╡ 4c06d6b3-8802-4e48-b926-0512203e345e
__LATEX_Par

# ╔═╡ 00000000-0000-0000-0000-000000000001
PLUTO_PROJECT_TOML_CONTENTS = """
[compat]
HypertextLiteral = "~0.8.0"
PlutoUI = "~0.7.9"

[deps]
HypertextLiteral = "ac1192a8-f4b3-4bfe-ba22-af5b92cd3ab2"
PlutoUI = "7f904dfe-b85e-4ff6-b463-dae2292396a8"
"""

# ╔═╡ 00000000-0000-0000-0000-000000000002
PLUTO_MANIFEST_TOML_CONTENTS = """
# This file is machine-generated - editing it directly is not advised

[[Base64]]
uuid = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"

[[Dates]]
deps = ["Printf"]
uuid = "ade2ca70-3891-5945-98fb-dc099432e06a"

[[HypertextLiteral]]
git-tree-sha1 = "1e3ccdc7a6f7b577623028e0095479f4727d8ec1"
uuid = "ac1192a8-f4b3-4bfe-ba22-af5b92cd3ab2"
version = "0.8.0"

[[InteractiveUtils]]
deps = ["Markdown"]
uuid = "b77e0a4c-d291-57a0-90e8-8db25a27a240"

[[JSON]]
deps = ["Dates", "Mmap", "Parsers", "Unicode"]
git-tree-sha1 = "81690084b6198a2e1da36fcfda16eeca9f9f24e4"
uuid = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
version = "0.21.1"

[[Logging]]
uuid = "56ddb016-857b-54e1-b83d-db4d58db5568"

[[Markdown]]
deps = ["Base64"]
uuid = "d6f4376e-aef5-505a-96c1-9c027394607a"

[[Mmap]]
uuid = "a63ad114-7e13-5084-954f-fe012c677804"

[[Parsers]]
deps = ["Dates"]
git-tree-sha1 = "c8abc88faa3f7a3950832ac5d6e690881590d6dc"
uuid = "69de0a69-1ddd-5017-9359-2bf0b02dc9f0"
version = "1.1.0"

[[PlutoUI]]
deps = ["Base64", "Dates", "InteractiveUtils", "JSON", "Logging", "Markdown", "Random", "Reexport", "Suppressor"]
git-tree-sha1 = "44e225d5837e2a2345e69a1d1e01ac2443ff9fcb"
uuid = "7f904dfe-b85e-4ff6-b463-dae2292396a8"
version = "0.7.9"

[[Printf]]
deps = ["Unicode"]
uuid = "de0858da-6303-5e67-8744-51eddeeeb8d7"

[[Random]]
deps = ["Serialization"]
uuid = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"

[[Reexport]]
git-tree-sha1 = "5f6c21241f0f655da3952fd60aa18477cf96c220"
uuid = "189a3867-3050-52da-a836-e630ba90ab69"
version = "1.1.0"

[[Serialization]]
uuid = "9e88b42a-f829-5b0c-bbe9-9e923198166b"

[[Suppressor]]
git-tree-sha1 = "a819d77f31f83e5792a76081eee1ea6342ab8787"
uuid = "fd094767-a336-5f1f-9728-57cf17d0bbfb"
version = "0.2.0"

[[Unicode]]
uuid = "4ec0a83e-493e-50e2-b9ac-8f72acf5a8f5"
"""

# ╔═╡ Cell order:
# ╠═1a6943bf-ede7-4690-80de-e9ec23cc66da
# ╠═b0ce1300-df3c-11eb-30ca-e7fee566afae
# ╠═aab42b5e-3d81-454f-97c7-e39bbb0ba425
# ╠═3edb1f40-3cb0-4ef9-a917-047fbdfc7c33
# ╠═4d007aa4-831f-4933-a96d-38e9ed3e8d46
# ╠═3bbc1d6d-86c6-4ad8-b8a8-e2154bd11352
# ╠═bc8a2c67-f944-4999-87c9-1cc17467cbe8
# ╠═c7581a61-f600-40f1-960f-127e9de2c2e8
# ╠═acaa17f6-9e56-4ed1-8545-ea2f0653f3b7
# ╠═4c06d6b3-8802-4e48-b926-0512203e345e
# ╠═c7fd078d-862f-42a2-a515-221ed411b4fb
# ╠═899f5d16-7018-4297-9939-0a4b5eb30620
# ╟─00000000-0000-0000-0000-000000000001
# ╟─00000000-0000-0000-0000-000000000002

use with pluto#1032

(@v1.6) pkg> activate --temp
  Activating new environment at `/tmp/jl_pesYut/Project.toml`

(jl_pesYut) pkg> add https://github.com/Pangoraw/Pluto.jl#macros
    Updating git-repo `https://github.com/Pangoraw/Pluto.jl`
    Updating registry at `~/.julia/registries/General`

original source: https://github.com/fonsp/disorganised-mess/blob/main/katex%20fun.jl

This is awesome stuff!

May I ask what the justification is for having double backslashes everywhere within a tex_str block? Is it not possible to parse escapes/tex commands with single backslashes?

This is caused by ex = Meta.parse("\"" * s * "\"") to support interpolation of Julia objects.
Using the following should not require double backslashes:

macro tex_str(s)
	tex(s)
end