Add tab function to vim.moon and refactor

vim.column is now called vim.col and has been turned into a wrapper for
the tab function. The vim.row wrapper has been added and does what you'd
expect. vim.box is also a wrapper for vim.tab now.
Some other refactoring has been done.

lua/vim.moon

@@ -1,4 +1,15 @@
 -- vim: set noexpandtab :miv --
+
+-- ┌──────────────────────────┐
+-- │ Generic Helper Functions │
+-- └──────────────────────────┘
+
+match_all = (str, pat, init=0) ->
+	s,e = str\find(pat, init)
+	if s then
+		return str\sub(s,e), match_all(str, pat, e+1)
+match_lines = (str) -> match_all(str, '[^\n]+')
+
 tree = (tab, pref='') ->
 	print tab.title and tab.title or '┐'
 
@@ -13,37 +24,49 @@ tree = (tab, pref='') ->
 			else
 				print tostring element
 
+pad = (str='', len) ->
+	str..string.rep(" ", len-#str)
+
+-- ┌──────────────────┐
+-- │ Actual Functions │
+-- └──────────────────┘
+
 import max from math
-column = (col) ->
-	if type(col)!="table" then col = {col}
-	pad = (str, len) ->
-		str..string.rep(" ", len-#str)
-	width = 0
-	for box in *col
-		if type(box)!="table" then box = {box}
-		for elem in *box
-			width = max(width, #elem)
 
-	print "┌─"..string.rep("─",width).."─┐"
-	for idx,box in ipairs(col)
-		if type(box)!="table" then box={box}
-		last = idx==#col
-		for elem in *box
-			io.write "│ "
-			io.write pad elem, width
-			io.write " │"
-			print!
-		unless last
-			print "├─"..string.rep("─",width).."─┤"
-	print "└─"..string.rep("─",width).."─┘"
+chktbl = (obj) -> error("Object is not a table", 2) if type(obj) ~= 'table'
+to_tab = (obj) -> type(obj)=='table' and obj or {match_lines tostring obj}
 
-match_all = (str, pat, init=0) ->
-	s,e = str\find(pat, init)
-	if s then
-		return str\sub(s,e), match_all(str, pat, e+1)
+tab = (rows) ->
+	-- Get Measurements
+	chktbl(rows)
+	width = {}
+	height = {}
+	for row, fields in ipairs rows
+		chktbl(fields)
+		height[row] = 1
+		for col, lines in ipairs fields
+			lines = to_tab lines
+			height[row] = max(height[row], #lines)
+			for line in *lines do
+				width[col] = max(width[col] or 1, #line)
+			fields[col] = lines
+	bars = [string.rep('─', i+2) for i in *width]
+	-- Top Line
+	print '┌'..table.concat(bars, '┬')..'┐'
+	-- Rows
+	for row, fields in ipairs rows
+		for line=1,height[row]
+			io.write '│' -- Outer Left Border
+			for col, lines in ipairs fields
+				io.write ' '..pad(lines[line], width[col])..' '
+				io.write '│' if col < #fields
+			print '│' -- Outer Left Border
+		print '├'..table.concat(bars, '┼')..'┤' unless row == #rows
+	print '└'..table.concat(bars, '┴')..'┘'
 
-box = (box) ->
-	column { match_all box, '[^\n]+' }
+col = (col) -> tab([{elem} for elem in *col])
+row = (row) -> tab{row}
+box = (box) -> tab{{box}}
 
 CLASS = [[
 print vim.col {
@@ -68,7 +91,8 @@ draw = ->
 
 
 {
-	:tree, :column, :box, :draw, :CLASS
+	:tree, :box, :draw, :tab, :col, :row
+	:CLASS
 	-- Aliases
-	col: column
+	table: tab
 }