{:NomsuCode} = require "code_obj"
{:find, :sub, :match} = string
{:R,:P,:S} = require 'lpeg'
re = require 're'
MAX_LINE = 80
GOLDEN_RATIO = ((math.sqrt(5)-1)/2)
-- Parsing helper functions
utf8_char_patt = (
R("\194\223")*R("\128\191") +
R("\224\239")*R("\128\191")*R("\128\191") +
R("\240\244")*R("\128\191")*R("\128\191")*R("\128\191"))
operator_patt = S("'`~!@$^&*+=|<>?/-")^1 * -1
identifier_patt = (R("az","AZ","09") + P("_") + utf8_char_patt)^1 * -1
is_operator = (s)->
return not not operator_patt\match(s)
is_identifier = (s)->
return not not identifier_patt\match(s)
inline_escaper = re.compile("{~ (%utf8_char / ('\"' -> '\\\"') / ('\n' -> '\\n') / ('\t' -> '\\t') / ('\b' -> '\\b') / ('\a' -> '\\a') / ('\v' -> '\\v') / ('\f' -> '\\f') / ('\r' -> '\\r') / ('\\' -> '\\\\') / ([^ -~] -> escape) / .)* ~}", {utf8_char: utf8_char_patt, escape:(=> ("\\%03d")\format(@byte!))})
inline_escape = (s)->
return inline_escaper\match(s)
escaper = re.compile("{~ (%utf8_char / ('\\' -> '\\\\') / [\n\r\t -~] / (. -> escape))* ~}",
{utf8_char: utf8_char_patt, escape:(=> ("\\%03d")\format(@byte!))})
escape = (s)->
return escaper\match(s)
tree_to_inline_nomsu = (tree)->
switch tree.type
when "Action"
nomsu = NomsuCode\from(tree.source)
num_args = 0
for i,bit in ipairs tree
if type(bit) == "string"
clump_words = if type(tree[i-1]) == 'string'
is_operator(bit) != is_operator(tree[i-1])
else bit == "'"
nomsu\add " " if i > 1 and not clump_words
nomsu\add bit
else
num_args += 1
arg_nomsu = tree_to_inline_nomsu(bit)
if bit.type == "Block"
if i > 1 and i < #tree
nomsu\add " "
unless i == #tree
arg_nomsu\parenthesize!
else
nomsu\add " " if i > 1
if bit.type == "Action" or bit.type == "MethodCall"
arg_nomsu\parenthesize!
nomsu\add arg_nomsu
return nomsu
when "MethodCall"
return NomsuCode\from(tree.source, tree_to_inline_nomsu(tree[1]), "|", tree_to_inline_nomsu(tree[2]))
when "EscapedNomsu"
inner_nomsu = tree_to_inline_nomsu(tree[1])
unless tree[1].type == "List" or tree[1].type == "Dict" or tree[1].type == "Var"
inner_nomsu\parenthesize!
return NomsuCode\from(tree.source, "\\", inner_nomsu)
when "Block"
nomsu = NomsuCode\from(tree.source, ":")
for i,line in ipairs tree
nomsu\add(i == 1 and " " or "; ")
nomsu\add tree_to_inline_nomsu(line)
nomsu\parenthesize! if #tree > 1
return nomsu
when "Text"
add_text = (nomsu, tree)->
for i, bit in ipairs tree
if type(bit) == 'string'
escaped = inline_escape(bit)
nomsu\add inline_escape(bit)
elseif bit.type == "Text"
add_text(nomsu, bit)
else
interp_nomsu = tree_to_inline_nomsu(bit)
if bit.type != "Var" and bit.type != "List" and bit.type != "Dict"
interp_nomsu\parenthesize!
elseif bit.type == "Var" and type(tree[i+1]) == 'string' and not match(tree[i+1], "^[ \n\t,.:;#(){}[%]]")
interp_nomsu\parenthesize!
nomsu\add "\\", interp_nomsu
nomsu = NomsuCode\from(tree.source)
add_text(nomsu, tree)
return NomsuCode\from(tree.source, '"', nomsu, '"')
when "List", "Dict"
nomsu = NomsuCode\from(tree.source, (tree.type == "List" and "[" or "{"))
for i, item in ipairs tree
nomsu\add ", " if i > 1
nomsu\add tree_to_inline_nomsu(item)
nomsu\add(tree.type == "List" and "]" or "}")
return nomsu
when "DictEntry"
key, value = tree[1], tree[2]
nomsu = if key.type == "Text" and #key == 1 and is_identifier(key[1])
NomsuCode\from(key.source, key[1])
else tree_to_inline_nomsu(key)
nomsu\parenthesize! if key.type == "Action" or key.type == "MethodCall" or key.type == "Block"
if value
nomsu\add ": "
value_nomsu = tree_to_inline_nomsu(value)
value_nomsu\parenthesize! if value.type == "Block"
nomsu\add value_nomsu
return nomsu
when "IndexChain"
nomsu = NomsuCode\from(tree.source)
for i, bit in ipairs tree
nomsu\add "." if i > 1
local bit_nomsu
bit_nomsu = if i > 1 and bit.type == "Text" and #bit == 1 and type(bit[1]) == 'string' and is_identifier(bit[1])
bit[1]
else tree_to_inline_nomsu(bit)
assert bit.type != "Block"
switch bit.type
when "Action", "MethodCall", "IndexChain"
bit_nomsu\parenthesize!
when "Number"
bit_nomsu\parenthesize! if bit_nomsu\text!\match("%.")
nomsu\add bit_nomsu
return nomsu
when "Number"
s = if tree.hex and tree[1] < 0
("-0x%X")\format(-tree[1])
elseif tree.hex
("0x%X")\format(tree[1])
else tostring(tree[1])
return NomsuCode\from(tree.source, s)
when "Var"
-- TODO: remove this hack:
varname = tree[1]\gsub("_", " ")
if varname == "" or is_identifier(varname)
return NomsuCode\from(tree.source, "$", varname)
else
return NomsuCode\from(tree.source, "$(", varname, ")")
when "FileChunks"
error("Can't inline a FileChunks")
when "Comment"
-- TODO: implement?
return NomsuCode\from(tree.source)
when "Error"
error("Can't compile errors")
else
error("Unknown type: #{tree.type}")
tree_to_nomsu = (tree)->
nomsu = NomsuCode\from(tree.source)
-- For concision:
recurse = (t)->
space = MAX_LINE - nomsu\trailing_line_len!
try_inline = true
for subtree in coroutine.wrap(-> (t\map(coroutine.yield) and nil))
if subtree.type == "Block"
if #subtree > 1
try_inline = false
local inline_nomsu
if try_inline
inline_nomsu = tree_to_inline_nomsu(t)
if #inline_nomsu\text! <= space or #inline_nomsu\text! <= 8
if t.type == "Action" or t.type == "MethodCall"
inline_nomsu\parenthesize!
return inline_nomsu
if t.type == "Text" and #inline_nomsu\text! + 2 < MAX_LINE
return inline_nomsu
indented = tree_to_nomsu(t)
if t.type == "Action" or t.type == "MethodCall"
if indented\is_multiline!
return NomsuCode\from(t.source, "(..)\n ", indented)
else indented\parenthesize!
if inline_nomsu and indented\text!\match("^[^\n]*\n[^\n]*$") and nomsu\trailing_line_len! <= 8
return inline_nomsu
return indented
switch tree.type
when "FileChunks"
if tree.shebang
nomsu\add tree.shebang
for chunk_no, chunk in ipairs tree
nomsu\add "\n\n#{("~")\rep(80)}\n\n" if chunk_no > 1
if chunk.type == "Block"
nomsu\add NomsuCode\from(chunk.source, table.unpack(tree_to_nomsu(chunk).bits, 2))
else
nomsu\add tree_to_nomsu(chunk)
nomsu\add('\n') unless nomsu\match("\n$")
return nomsu
when "Action"
next_space = ""
word_buffer = {}
num_args = 0
for i,bit in ipairs tree
if type(bit) == "string"
if #word_buffer > 0 and is_operator(bit) == is_operator(word_buffer[#word_buffer])
table.insert word_buffer, " "
table.insert word_buffer, bit
continue
if #word_buffer > 0
words = table.concat(word_buffer)
if next_space == " "
if nomsu\trailing_line_len! + #words > MAX_LINE and nomsu\trailing_line_len! > 8
next_space = " \\\n.."
elseif word_buffer[1] == "'"
next_space = ""
nomsu\add next_space, words
word_buffer = {}
next_space = " "
num_args += 1
bit_nomsu = recurse(bit)
if bit.type == "Block" and not bit_nomsu\is_multiline!
-- Rule of thumb: nontrivial one-liner block arguments should be no more
-- than golden ratio * the length of the proceeding part of the line
if #bit_nomsu\text! > nomsu\trailing_line_len! * GOLDEN_RATIO and #bit_nomsu\text! > 8
bit_nomsu = tree_to_nomsu(bit)
if (next_space == " " and not bit_nomsu\is_multiline! and
nomsu\trailing_line_len! + #bit_nomsu\text! > MAX_LINE and
nomsu\trailing_line_len! > 8)
if bit.type == 'Action' or bit.type == "MethodCall"
bit_nomsu = NomsuCode\from bit.source, "(..)\n ", tree_to_nomsu(bit)
else
next_space = " \\\n.."
unless next_space == " " and bit.type == "Block"
nomsu\add next_space
nomsu\add bit_nomsu
next_space = (bit_nomsu\is_multiline! or bit.type == 'Block') and "\n.." or " "
if #word_buffer > 0
words = table.concat(word_buffer)
if next_space == " "
if nomsu\trailing_line_len! + #words > MAX_LINE and nomsu\trailing_line_len! > 8
next_space = " \\\n.."
elseif word_buffer[1] == "'"
next_space = ""
nomsu\add next_space, words
next_space = " "
return nomsu
when "MethodCall"
target_nomsu = recurse(tree[1])
if tree[1].type == "Block" and not target_nomsu\is_multiline!
target_nomsu\parenthesize!
nomsu\add target_nomsu
nomsu\add(target_nomsu\is_multiline! and "\n..|" or "|")
nomsu\add tree_to_nomsu(tree[2])
return nomsu
when "EscapedNomsu"
nomsu = recurse(tree[1])
if tree[1].type == 'Block' and not nomsu\is_multiline!
nomsu\parenthesize!
return NomsuCode\from tree.source, "\\", nomsu
when "Block"
prev_line, needs_space = nil, {}
for i, line in ipairs tree
line_nomsu = tree_to_nomsu(line)
if i > 1
nomsu\add "\n"
-- Rule of thumb: add a blank line between two lines if both are
-- multi-line non-comments, or if a comment comes after a non-comment.
if tree[i-1].type != "Comment"
needs_space[i] = (line_nomsu\is_multiline! and prev_line\is_multiline!)
if tree[i].type == "Comment" or needs_space[i] or needs_space[i-1]
nomsu\add "\n"
nomsu\add line_nomsu
prev_line = line_nomsu
return NomsuCode\from(tree.source, ":\n ", nomsu)
when "Text"
-- Multi-line text has more generous wrap margins
max_line = math.floor(1.25*MAX_LINE)
add_text = (tree)->
for i, bit in ipairs tree
if type(bit) == 'string'
bit = escape(bit)
for j, line in ipairs bit\lines!
if j > 1
nomsu\add "\n"
elseif #line > 10 and nomsu\trailing_line_len! > max_line
nomsu\add "\\\n.."
while #line > 0
space = max_line - nomsu\trailing_line_len!
split = find(line, "[%p%s]", space)
if not split or split > space + 10
split = space + 10
if #line - split < 10
split = #line
bite, line = sub(line, 1, split), sub(line, split+1, -1)
nomsu\add bite
nomsu\add "\\\n.." if #line > 0
elseif bit.type == "Text"
add_text(bit)
else
nomsu\add "\\"
interp_nomsu = recurse(bit)
unless interp_nomsu\is_multiline!
if bit.type == "Var"
if type(tree[i+1]) == 'string' and not match(tree[i+1], "^[ \n\t,.:;#(){}[%]]")
interp_nomsu\parenthesize!
elseif bit.type == "EscapedNomsu" or bit.type == "Block" or bit.type == "IndexChain"
interp_nomsu\parenthesize!
nomsu\add interp_nomsu
if interp_nomsu\is_multiline!
nomsu\add "\n.."
add_text(tree)
return NomsuCode\from(tree.source, '"\n ', nomsu, '"')
when "List", "Dict"
if #tree == 0
nomsu\add(tree.type == "List" and "[]" or "{}")
return nomsu
sep = ''
for i, item in ipairs tree
item_nomsu = tree_to_inline_nomsu(item)
if #item_nomsu\text! > MAX_LINE
item_nomsu = recurse(item)
if item.type == 'Comment'
item_nomsu = tree_to_nomsu(item)
nomsu\add sep
nomsu\add item_nomsu
if item_nomsu\is_multiline! or item.type == 'Comment' or nomsu\trailing_line_len! + #tostring(item_nomsu) >= MAX_LINE
sep = '\n'
else
sep = ', '
return if tree.type == "List" then
NomsuCode\from(tree.source, "[..]\n ", nomsu)
else
NomsuCode\from(tree.source, "{..}\n ", nomsu)
when "DictEntry"
key, value = tree[1], tree[2]
nomsu = if key.type == "Text" and #key == 1 and is_identifier(key[1])
NomsuCode\from(key.source, key[1])
else tree_to_inline_nomsu(key)
nomsu\parenthesize! if key.type == "Block"
if value
value_nomsu = tree_to_nomsu(value)
if (value.type == "Block" or value.type == "EscapedNomsu") and not value_nomsu\is_multiline!
value_nomsu\parenthesize!
nomsu\add ": ", value_nomsu
return nomsu
when "Comment"
nomsu\add "#", (tree[1]\gsub("\n", "\n "))
return nomsu
when "IndexChain", "Number", "Var", "Comment", "Error"
return tree_to_inline_nomsu tree
else
error("Unknown type: #{tree.type}")
return {:tree_to_nomsu, :tree_to_inline_nomsu}