images for dark+light mode

_extensions/pandoc-ext/list-table/_extension.yaml

@@ -0,0 +1,7 @@
+title: list-table
+author: Martin Fischer, pandoc extensions contributors
+version: 1.0.0
+quarto-required: ">=1.3"
+contributes:
+  filters:
+    - list-table.lua

_extensions/pandoc-ext/list-table/list-table.lua

@@ -0,0 +1,270 @@
+-- lua filter for RST-like list-tables in Markdown.
+-- Copyright (C) 2021 Martin Fischer, released under MIT license
+
+if PANDOC_VERSION and PANDOC_VERSION.must_be_at_least then
+    PANDOC_VERSION:must_be_at_least("2.11")
+else
+    error("pandoc version >=2.11 is required")
+end
+
+-- Get the list of cells in a row.
+local row_cells = function (row) return row.cells or {} end
+
+-- "Polyfill" for older pandoc versions.
+if PANDOC_VERSION <= '2.16.2' then
+  -- previous pandoc versions used simple Attr/list pairs
+  pandoc.Row = function (cells) return {{}, cells} end
+  pandoc.TableHead = function (rows) return {{}, rows or {}} end
+  pandoc.TableFoot = function (rows) return {{}, rows or {}} end
+  pandoc.Cell = function (contents, align, rowspan, colspan, attr)
+    return {
+      attr = attr or pandoc.Attr(),
+      alignment = align or pandoc.AlignDefault,
+      contents = contents or {},
+      col_span = colspan or 1,
+      row_span = rowspan or 1
+    }
+  end
+  row_cells = function (row) return row[2] end
+end
+
+local alignments = {
+    d = 'AlignDefault',
+    l = 'AlignLeft',
+    r = 'AlignRight',
+    c = 'AlignCenter'
+}
+
+
+-- This is like assert() but it can take a Block or Blocks 'where' argument
+-- and will output the corresponding markdown (truncated at 1024 characters).
+local function assert_(assertion, message, where)
+    message = message or 'assertion failed!'
+    if not assertion then
+        local extra = ''
+        if where then
+            local blocks = pandoc.Blocks(where)
+            local markdown = pandoc.write(pandoc.Pandoc(blocks), 'markdown')
+            extra = ' at\n' .. markdown:sub(1, 1024) ..
+                (#markdown > 1024 and '...' or '')
+        end
+        error(message .. extra, 2)
+    end
+end
+
+-- Skip data-pos Divs inserted by the sourcepos extension
+local function block_skip_data_pos(block)
+    if (block.t == "Div" and block.attr.attributes["data-pos"]) then
+        block = block.content[1]
+    end
+    return block
+end
+
+local function blocks_skip_data_pos(blocks)
+    local new_blocks = {}
+    for _, block in ipairs(blocks) do
+        table.insert(new_blocks, block_skip_data_pos(block))
+    end
+    return new_blocks
+end
+
+local function get_colspecs(div_attributes, column_count)
+    -- list of (align, width) pairs
+    local colspecs = {}
+
+    for i = 1, column_count do
+        table.insert(colspecs, {pandoc.AlignDefault, nil})
+    end
+
+    if div_attributes.aligns then
+        local i = 1
+        for a in div_attributes.aligns:gmatch('[^,]+') do
+            assert_(alignments[a] ~= nil,
+                    "unknown column alignment " .. tostring(a))
+            colspecs[i][1] = alignments[a]
+            i = i + 1
+        end
+        div_attributes.aligns = nil
+    end
+
+    if div_attributes.widths then
+        local total = 0
+        local widths = {}
+        for w in div_attributes.widths:gmatch('[^,]+') do
+            table.insert(widths, tonumber(w))
+            total = total + tonumber(w)
+        end
+        for i = 1, column_count do
+            colspecs[i][2] = widths[i] / total
+        end
+        div_attributes.widths = nil
+    end
+
+    return colspecs
+end
+
+local function new_table_body(rows, attr, header_col_count)
+    attr = attr or {}
+    return {
+        attr = attr,
+        body = rows,
+        head = {},
+        row_head_columns = header_col_count
+    }
+end
+
+local function new_cell(contents)
+    local attr = {}
+    local colspan = 1
+    local rowspan = 1
+    local align = pandoc.AlignDefault
+
+    contents = blocks_skip_data_pos(contents)
+
+    -- At the time of writing this Pandoc does not support attributes
+    -- on list items, so we use empty spans as a workaround.
+    if contents[1] and contents[1].content then
+        if contents[1].content[1] and contents[1].content[1].t == "Span" then
+            if #contents[1].content[1].content == 0 then
+                attr = contents[1].content[1].attr
+                table.remove(contents[1].content, 1)
+                colspan = attr.attributes.colspan or 1
+                attr.attributes.colspan = nil
+                rowspan = attr.attributes.rowspan or 1
+                attr.attributes.rowspan = nil
+                align = alignments[attr.attributes.align] or pandoc.AlignDefault
+                attr.attributes.align = nil
+            end
+        end
+    end
+
+    return pandoc.Cell(contents, align, rowspan, colspan, attr)
+end
+
+local function process(div)
+    if (div.attr.classes[1] ~= "list-table" and
+        div.attr.classes[1] ~= "list-table-body") then return nil end
+    local class = div.attr.classes[1]
+    table.remove(div.attr.classes, 1)
+
+    if #div.content == 0 then return nil end
+
+    local content = blocks_skip_data_pos(div.content)
+
+    local caption = {}
+    if content[1].t == "Para" then
+        local para = table.remove(content, 1)
+        caption = {pandoc.Plain(para.content)}
+    end
+
+    if #content == 0 then return nil end
+
+    assert_(content[1].t == "BulletList",
+            "expected bullet list, found " .. content[1].t, content[1])
+    local list = content[1]
+
+    -- rows points to the current body's rows
+    local bodies = {attr=nil, {rows={}}}
+    local rows = bodies[#bodies].rows
+
+    for i = 1, #list.content do
+        local attr = nil
+        local items = list.content[i]
+        if (#items > 1) then
+            local item = block_skip_data_pos(items[1])
+            assert_(item.content, "expected list item to have row attrs",
+                    item)
+            assert_(#item.content == 1, "expected row attrs to contain " ..
+                        "only one inline", item.content)
+            assert_(item.content[1].t == "Span", "expected row attrs to " ..
+                        "contain a span", item.content[1])
+            assert_(#item.content[1].content == 0, "expected row attrs " ..
+                        "span to be empty", item.content[1])
+            attr = item.content[1].attr
+            table.remove(items, 1)
+        end
+
+        assert_(#items == 1, "expected item to contain only one block", items)
+
+        local item = block_skip_data_pos(items[1])
+        if (item.t ~= 'Table') then
+            assert_(item.t == "BulletList", "expected bullet list, found " ..
+                        item.t, item)
+            local cells = {}
+            for _, cell_content in pairs(item.content) do
+                table.insert(cells, new_cell(cell_content))
+            end
+            local row = pandoc.Row(cells, attr)
+            table.insert(rows, row)
+
+        else
+            local tab = item
+            -- XXX is there a better way to check that there's no caption?
+            assert_((not tab.caption.long or #tab.caption.long == 0) and
+                        (not tab.caption.short or #tab.caption.short == 0),
+                    "table bodies can't have captions (they'd be " ..
+                        "ignored)", tab)
+            -- XXX would have to check against default colspecs to know whether
+            --     any have been defined?
+            -- assert_(#tab.colspecs == 0, "table bodies can't (yet) have " ..
+            --         "column specs", tab)
+            -- XXX should allow empty headers; this can happen with pipe tables
+            -- assert_(not tab.head or #tab.head.rows == 0,
+            --         "table bodies can't (yet) have headers", tab)
+            assert_(#tab.bodies == 1, "table bodies can't contain other " ..
+                        "table bodies", tab)
+
+            if #rows > 0 then
+                table.insert(bodies, {attr=nil, rows={}})
+                rows = bodies[#bodies].rows
+            end
+
+            bodies[#bodies].attr = tab.attr
+            for _, row in ipairs(tab.bodies[1].body) do
+                table.insert(rows, row)
+            end
+        end
+    end
+
+    -- switch back to the first body
+    rows = bodies[1].rows
+
+    local header_row_count = tonumber(div.attr.attributes['header-rows']) or
+        (class == 'list-table' and 1 or 0)
+    div.attr.attributes['header-rows'] = nil
+
+    local header_col_count = tonumber(div.attr.attributes['header-cols']) or 0
+    div.attr.attributes['header-cols'] = nil
+
+    local column_count = 0
+    for i = 1, #row_cells(rows[1] or {}) do
+        column_count = column_count + row_cells(rows[1])[i].col_span
+    end
+
+    local colspecs = get_colspecs(div.attr.attributes, column_count)
+    local thead_rows = {}
+    for i = 1, header_row_count do
+        table.insert(thead_rows, table.remove(rows, 1))
+    end
+
+    local new_bodies = {}
+    for _, body in ipairs(bodies) do
+        if #body.rows > 0 then
+            table.insert(new_bodies, new_table_body(body.rows, body.attr,
+                                                    header_col_count))
+        end
+        -- XXX this should be a body property
+        header_col_count = 0
+    end
+
+    return pandoc.Table(
+        {long = caption, short = {}},
+        colspecs,
+        pandoc.TableHead(thead_rows),
+        new_bodies,
+        pandoc.TableFoot(),
+        div.attr
+    )
+end
+
+return {{Div = process}}

docs/authoring/_figure-examples/_examples.qmd

@@ -12,7 +12,13 @@ quarto run take-screenshots.R
 
 ## Figure Basics
 
+::: light-content
 ![Elephant](elephant.png){width="400px"}
+:::
+
+::: dark-content
+![Elephant](elephant-dark.png){width="400px"}
+:::
 
 
 ## Subfigures

docs/authoring/_table-crossrefs.md

@@ -16,4 +16,10 @@ See @tbl-letters.
 
 Which looks like this when rendered to HTML:
 
-![](images/crossref-table.png){fig-alt="A table with 3 columns and four rows. The text 'Table 1: My Caption' is above the header column. The text 'See tbl. 1' is aligned to the left underneath the last column." width="500"}
+::: light-content
+![](images/crossref-table.png){fig-alt="A table with 3 columns and four rows. The text 'Table 1: My Caption' is above the header column. The text 'See tbl. 1' is aligned to the left underneath the last column." width="100%"}
+:::
+
+::: dark-content
+![](images/crossref-table-dark.png){fig-alt="A table with 3 columns and four rows. The text 'Table 1: My Caption' is above the header column. The text 'See tbl. 1' is aligned to the left underneath the last column." width="100%"}
+:::