add extensions

_extensions/quarto-ext/latex-environment/_extension.yml

@@ -0,0 +1,9 @@
+title: LaTeX Environment
+author: RStudio, PBC
+version: 1.1.0
+quarto-required: ">=1.2.198"
+contributes:
+  filters:
+    - latex-environment.lua
+  format:
+    pdf: default

_extensions/quarto-ext/latex-environment/latex-environment.lua

@@ -0,0 +1,133 @@
+-- environment.lua
+-- Copyright (C) 2020 by RStudio, PBC
+
+local classEnvironments = pandoc.MetaMap({})
+local classCommands = pandoc.MetaMap({})
+
+-- helper that identifies arrays
+local function tisarray(t)
+  local i = 0
+  for _ in pairs(t) do
+    i = i + 1
+    if t[i] == nil then return false end
+  end
+  return true
+end
+
+-- reads the environments
+local function readEnvironments(meta)
+  local env = meta['environments']
+  if env ~= nil then
+    if tisarray(env) then
+      -- read an array of strings
+      for i, v in ipairs(env) do
+        local value = pandoc.utils.stringify(v)
+        classEnvironments[value] = value
+      end
+    else
+      -- read key value pairs
+      for k, v in pairs(env) do
+        local key = pandoc.utils.stringify(k)
+        local value = pandoc.utils.stringify(v)
+        classEnvironments[key] = value
+      end
+    end
+  end
+end
+
+local function readCommands(meta)
+  local env = meta['commands']
+  if env ~= nil then
+    if tisarray(env) then
+      -- read an array of strings
+      for i, v in ipairs(env) do
+        local value = pandoc.utils.stringify(v)
+        classCommands[value] = value
+      end
+    else
+      -- read key value pairs
+      for k, v in pairs(env) do
+        local key = pandoc.utils.stringify(k)
+        local value = pandoc.utils.stringify(v)
+        classCommands[key] = value
+      end
+    end
+  end
+end
+
+local function readEnvsAndCommands(meta)
+  readEnvironments(meta)
+  readCommands(meta)
+end
+
+-- use the environments from metadata to
+-- emit a custom environment for latex
+local function writeEnvironments(divEl)
+  if quarto.doc.is_format("latex") then
+    for k, v in pairs(classEnvironments) do
+      if divEl.attr.classes:includes(k) then
+        -- process this into a latex environment
+        local beginEnv = '\\begin' .. '{' .. v .. '}'
+        local endEnv = '\n\\end{' .. v .. '}'
+        
+        -- check if custom options or arguments are present
+        -- and add them to the environment accordingly
+        local opts = divEl.attr.attributes['options']
+        if opts then
+          beginEnv = beginEnv .. '[' .. opts .. ']'
+        end
+
+        local args = divEl.attr.attributes['arguments']
+        if args then
+          beginEnv = beginEnv .. '{' .. args .. '}'
+        end
+        
+        -- if the first and last div blocks are paragraphs then we can
+        -- bring the environment begin/end closer to the content
+        if divEl.content[1].t == "Para" and divEl.content[#divEl.content].t == "Para" then
+          table.insert(divEl.content[1].content, 1, pandoc.RawInline('tex', beginEnv .. "\n"))
+          table.insert(divEl.content[#divEl.content].content, pandoc.RawInline('tex', "\n" .. endEnv))
+        else
+          table.insert(divEl.content, 1, pandoc.RawBlock('tex', beginEnv))
+          table.insert(divEl.content, pandoc.RawBlock('tex', endEnv))
+        end
+        return divEl
+      end
+    end
+  end
+end
+
+-- use the environments from metadata to
+-- emit a custom environment for latex
+local function writeCommands(spanEl)
+  if quarto.doc.is_format("latex") then
+    for k, v in pairs(classCommands) do
+      if spanEl.attr.classes:includes(k) then
+
+        -- resolve the begin command
+        local beginCommand = pandoc.RawInline('latex', '\\' .. pandoc.utils.stringify(v) .. '{')
+        local opts = spanEl.attr.attributes['options']
+        if opts then
+          beginCommand = pandoc.RawInline('latex', '\\' .. pandoc.utils.stringify(v) .. '[' .. opts .. ']{')
+        end
+
+        -- the end command
+        local endCommand = pandoc.RawInline('latex', '}')
+
+        -- attach the raw inlines to the span contents
+        local result = spanEl.content
+        table.insert(result, 1, beginCommand)
+        table.insert(result, endCommand)
+
+        return result
+      end
+    end
+  end
+end
+
+-- Run in two passes so we process metadata
+-- and then process the divs
+return {
+  { Meta = readEnvsAndCommands },
+  { Div = writeEnvironments, Span = writeCommands }
+}