Re: ["all"] as an Lvalue?

[Steve Litt <slitt@...>]

On Tue, 29 Mar 2016 12:04:13 +1100
Daurnimator <quae@daurnimator.com> wrote:

> On 29 March 2016 at 11:55, Steve Litt <slitt@troubleshooters.com>
> wrote:
> > Hi all,
> >
> > I'm writing a document on Luakit, and in my section on making fonts
> > bigger, I need to give instructions to edit the domain_props table,
> > which looks something like this:
> >
> > =====================================================
> > domain_props = {
> >     ["all"] = {
> >         enable_scripts          = false,
> >         enable_plugins          = false,
> >         enable_private_browsing = false,
> >         user_stylesheet_uri     = "",
> >     },
> >     ["youtube.com"] = {
> >         enable_scripts = true,
> >         enable_plugins = true,
> >     },
> > }
> > =====================================================
> >
> > It looks like domain_props is a table whose two elements are each
> > tables, named ["all"] and ["youtube.com"] respectively. I've never
> > seen something like ["all"] being the name of a table element or a
> > variable name before. What's going on, is ["all"] an anonymous
> > table containing element "all"? I just don't understand this
> > syntax, and why somebody would do this. What am I missing?  
> 
> { foo = "bar" }
> is actually just short for:
> { ["foo"] = "bar" }
> 
> The first shorter form however only works for keys that are valid
> identifiers. Which means you have to use the 2nd form for:
>   - keywords (e.g. {["end"] = 1234})
>   - non-valid identifiers
>       - e.g. starting with a number: {["1thing"] = item}
>       - e.g. containing a ".": {["youtube.com"] = "a website"}
>   - non-string keys. e.g. {[50] = "number as key"}
> 

Thanks Coda, Jonathan and Daurnimator:

I'd seen that many times as states["florida"], but I'd never before
seen it as {["firstname"] = "steve"}. Now that you explained it, it
makes perfect sense and I got everything to work in Luakit.

Thanks!

SteveT

Steve Litt 
March 2016 featured book: Quit Joblessness: Start Your Own Business
http://www.troubleshooters.com/startbiz