Code: Select all
w.x.y.z += 3Code: Select all
w.x.y.z = w.x.y.z + 3Code: Select all
if x == 3
code
endCode: Select all
code if x == 3I once patched Lua make then after if, and do after while and for, optional, just to see how invasive a patch it would be. Turns out it's a few lines of code, so I argued on the Lua mailing list for this change to be made to the language. This was the answer:BlackBulletIV wrote:As for the "then" thing, I don't mind much, I prefer not typing it though. Ruby handles that one fine:Code: Select all
if x == 3 code end
Although then was completely redundant in Lua 4, this changed when the grammar was changed to allow call and assignment statements to start with a parenthesized expression; this change made the ; statement terminator only semi-optional. The following could not be written without then because ; can only go after a statement; without the then it would be ambiguous:
Moreover, do cannot be optional in a for or while statement because the block could itself start with a do statement:Code: Select all
if x then (funcs[x] or default_func)() end
Code: Select all
while x > 100 do do local y = f(x) g(y) h(y) end -- ... end
Sure, but you can do that in the editor instead of exposing people who read your code to exactly what keystrokes you used to produce it. You could also have your editor expand "foo += " to "foo = foo + "Jasoco wrote:Syntactic bloat, shmyntactic bloat. It's all about saving time. I'd rather save typing strokes even if it means putting all love functions in global two keystroke shortcuts. WHICH I DO.
No, it's that it would allow ambiguous syntax. In which case it's not at all obvious what the compiler should do. These situations cause debugging to be very hard, because the code doesn't look wrong, and there is probably not even an error at that exact location.BlackBulletIV wrote:The main problem now I guess, is that they have to maintain backwards compatibility with grammar.
Hey, that's a cool idea!sharpobject wrote:You could also have your editor expand "foo += " to "foo = foo + "
Sorry, I probably said that without giving the context for what I was thinking. I was thinking of how impossible it would to switch to something like Ruby has, now that Lua is mature; for example begin ... end, and all that stuff. If that happened, it would cause compatibility problems all over the place.Robin wrote:No, it's that it would allow ambiguous syntax. In which case it's not at all obvious what the compiler should do. These situations cause debugging to be very hard, because the code doesn't look wrong, and there is probably not even an error at that exact location.BlackBulletIV wrote:The main problem now I guess, is that they have to maintain backwards compatibility with grammar.
It's because the codeBlackBulletIV wrote:I don't quite get the first one, but anyway.
Code: Select all
if x (funcs[x] or default_func)() endCode: Select all
function x(other_func)
return function()
other_func('default', 'arguments') ~= 'foo'
end
end
if x(funcs[x] or default_func)() then endCode: Select all
--main.lua
table.insert(package.loaders, function(name)
name = name:match("^meta%-(.+)$")
if not name then return nil end
local tokenized_name = name:gsub("%.", "/") .. ".lua"
if not love.filesystem.exists(tokenized_name) then
return nil
end
local contents = love.filesystem.read(tokenized_name)
do --replacements
contents = contents:gsub("([%w%.:%[%]]+)%s*%+=", "%1 = %1 + ")
contents = contents:gsub("([%w%.:%[%]]+)%s*%-=", "%1 = %1 - ")
contents = contents:gsub("([%w%.:%[%]]+)%+%+", "%1 = %1 + 1")
contents = contents:gsub("([%w%.:%[%]]+)%-%-", "%1 = %1 - 1")
end
print(contents)
return loadstring(contents)
end)
require "meta-game"
--game.lua
function love.load()
timer = 0
frames = 0
end
function love.update(dt)
timer += dt
frames++
end
function love.draw()
love.graphics.print("Time: " .. timer, 50, 50)
love.graphics.print("Frames: " .. frames, 50, 64)
love.graphics.print("Average FPS: " .. math.floor(frames/timer), 50, 78)
end