Re: Why do we have ipairs?

On Wed, Jun 11, 2014 at 1:42 AM, Axel Kittenberger <axkibe@gmail.com> wrote:

Iterators are not bound to for loops.

for k, v in ipairs( t )
do
print(k, v )
end

is syntactic sugar for:

local it = ipairs( t )
local k, v = it( t, 0 )
while k ~= nil
do
print(k, v )
k, v = it( t, k )
end

is syntactic sugar for:

local it = ipairs( t )
local k, v
k, v = it( t, 0 )
::loop::
print(k, v )
k, v = it( t, k )
if( k ~= nil )
then
goto loop

end

I think that in order for one thing to be the "syntactic sugar" of another, they need to do the same thing, not just have the same outcome. A switch statement wouldn't be sugar for an if/else. A "repeat until" loop isn't sugar for a while loop or a for loop. They over lap, and perhaps one can do without the other if at least one is present. They are not sugar.

Examples of sugar:

local x

x = function(...)

--do stuff

return x(...)

end

--is sugar for

local function x(...)

...

`local x:y(args)` is sugar for `local x.y(x, args)`

`{ foo = "bar"}` is sugar for `{ ["foo"] = "bar"}`

--Andrew