topic Re: Opposite of Default Local in Discussions

Opposite of Default Local

msharp — Fri, 30 Sep 2016 21:15:05 GMT

So, just some syntactical sugar.

It would be really nice if there was an opposite of declaring local variables for functions.

i.e. instead of:

example= function({a,b}, {c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w},

c = a+b;

d = c+a;

//...

x = v+w;

y = x+b;

);

print(x,y);

I could write:

example= function({a,b}, {Default Local, x, y},

c = a+b;

d = c+a;

//...

x = v+w;

y = x+b;

);

print(x,y);

Re: Opposite of Default Local

msharp — Fri, 30 Sep 2016 21:52:54 GMT

Another example:

x="global scope";

y="global scope";

Names Default to Here(1);

x="here scope";

y="here scope";

print(::x, x, ::y, y);

f = function({}, {Default Local, x},

x="here scope replaced";

y="function scope";

print(x, y);

);

f();

//x != y but it does

print(x, y);

Re: Opposite of Default Local

Phil_Brown — Fri, 30 Sep 2016 23:06:39 GMT

I think if you scope everything, you may get what you want.. Correct me if I'm not following but....For instance

::x="global scope";

::y="global scope";

Names Default to Here(1);

x="here scope";

y="here scope";

print(::x, here:x, ::y, here:y);

f = function({}, {Default Local},

here:x="here scope replaced";

::x = "global scope replaced";

x = "function scope x";

y = "function scope y";

print(here:x, ::x, x, y);

);

f();

print(x, y); // will be whatever was assigned to these vars in the HERE namespace.

print(::x, ::y); // will be whatever was assigned to these vars in the GLOBAL namespace.

// no way of accessing local vars (actually the point of local).

Re: Opposite of Default Local

Craige_Hales — Sat, 01 Oct 2016 10:35:24 GMT

I've been using explicit locals in functions. I think I'll try Default Local in my next project.

Re: Opposite of Default Local

msharp — Mon, 03 Oct 2016 13:51:45 GMT

I've never used here:x before, but that syntax makes total sense. Thanks!

Re: Opposite of Default Local

vince_faller — Wed, 19 Oct 2016 04:15:54 GMT

Same goes with local:x if you'd rather explicitly scope on the fly.

f = function({}, {},

x = "global scope replaced";

local:x = "function scope x";

local:y = "function scope y";

print(::x, local:x, y);

);

f();

You have to remember to call ::x explicitly because of the scoping rules for unscoped variables.