ahsoftware at sonic.net
Thu May 18 18:07:59 CEST 2017
On 05/18/2017 12:45 AM, Mark Waddingham via use-livecode wrote:
> You can define constants using:
> constant X is Y
> Currently Y has to be a literal - not an expression (just like LCS).
Didn't find it in the dictionary, but I do see that now in the language
reference. How would one define a quote constant?
constant quote is "\q" ?
The language guide explicitly states "Note: Constants are not currently
implemented, although the syntax is recognised." What am I supposed to
make of that?
>> Is it even possible to set the various delimiters? The documentation
>> only talks about retrieving them. The description talks about the
>> calling (script) handler's <type>Delimiter property... is this an
>> actual property of the object or is just a shorthand way of talking
>> about "the <type>Delimiter"?
> No - the context local properties are a LiveCode Script feature, they
> don't exist in LCB.
> The 'the <type>Delimiter' syntax gives you access to the values of those
> properties in the most recent LCS stack frame allowing LCB to do similar
> things as the engine can in its commands and functions.
That's unfortunate. In LCS I often change the itemdelimiter in order to
parse complex strings. The lack of the ability to manipulate things at
this level is a serious detriment to text parsing, which is one of the
main strengths of LCS.
>> The pointer type isn't documented.
> Well it is listed in the language reference ;)
Ah. So the dictionary isn't a good place to look for things. I'll spend
some time working my way through the language reference instead.
> LCB's syntax is quite minimal at the moment, it isn't meant to be a
> replacement for LCS (as mentioned before) - it is intended as a language
> which makes explicit the implicit patterns and abstractions which exist
> (albeit hand-coded in most cases) in the engine, so that they can be used
> to build the abstractions which we use everyday in LCS - and extend them
> in a natural way.
> For example, line and item chunks are actually an incarnation of what
> you might call a 'delimited chunk' - they have identical semantics, apart
> from where the delimiter to use is fetched from (the *delimiter property
> in local context).
> Similarly, word and token are 'tokenized chunks' - they action could be
> described by a regular expression.
See above (itemdelimiter).
ahsoftware at gmail.com
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