Re: Apologies for bad formatting: lecture slides etc.

[Luke <lemmett81@...>]

Is it right to say that we call a function when it appears in a
statement with parentheses after it? I'm also a little confused about
the difference between a variable and the value, e.g. if they can be
of a different type?

Sorry to go on: I just have zero experience of programming.. The
reference manual is unreadable in places, as yet. So I'm switching
between the lecture notes and book. Hopefully I won't have to keep
asking questions to the list. I had similar issues reading the manual
for ubuntu, and had to give up. I wonder if there's a webresource etc.
that includes a glossary necessary to understand manuals etc.

Cheers,
Luke

On Wed, 7 Nov 2018 at 03:27, Luke <lemmett81@gmail.com> wrote:
>
> yeah, thanks, I got that.
>
> function f()
> return 3 end
> thing = f
> print(type(thing), thing())
>
> thing is a function, but I was confused that you needed to add the parentheses to get print to print its value.
>
> I guess syntax just is the way it is?
>
>
>
> On Wed, 7 Nov 2018 at 03:16, Erutuon <arboreous.philologist@gmail.com> wrote:
>>
>> function square = <something or other> is not valid Lua syntax. "function" has to be followed by (at minimum) parentheses and then "end": function () end. See the section in the Lua manual on function definitions (https://www.lua.org/manual/5.3/manual.html#3.4.11).
>>
>> — Gabriel
>>
>>
>>
>> On Tue, Nov 6, 2018 at 9:05 PM Luke <lemmett81@gmail.com> wrote:
>>>
>>> > Think of map as a function maker.
>>> After making the function, the job of map is done.
>>> So, map never see the list {1, 5, 9}
>>>
>>> That makes sense. Why don't we use function to define square?
>>>
>>> function square = map(function (x) return x * x end)
>>>
>>> On Wed, 7 Nov 2018 at 02:59, Albert Chan <albertmcchan@yahoo.com> wrote:
>>>>
>>>>
>>>> > On Nov 6, 2018, at 9:29 PM, Luke <lemmett81@gmail.com> wrote:
>>>> >
>>>> > I believe that, because the definition does not begin with function, square is an anonymous function; it returns a value and is defined in an expression. So, I start with the table { 1, 5, 9 }. This is the argument to the square function. I'm guessing that the map function is called by square. But how / why does map get the table, when map only has one parameter, a function, and the table is not assigned to a variable? And how / why does map return a table value, as it seems to want to return a function?
>>>>
>>>> Think of map as a function maker.
>>>> After making the function, the job of map is done.
>>>> So, map never see the list {1, 5, 9}
>>>>
>>>> square stored what map function maker created.
>>>> square is now a function, that map x to x*x
>>>>
>>>> square( {1,5,9} ) ==> {1,25,81}
>>>>
>>>>
>>>>
>>>>
>>>>