True - I’d rather be first-class than complete anyway. And yes thanks for suggested way around incompleteness. I still suffered culture shock. The use-case I had was to replace send syntax with the more elegant set the ... of object to syntax. I found myself wanting a bit more power ...
Power is not always a good thing. I’m glad that the dignity of arrays has been restored. On Tue, 3 Apr 2018 at 10:25, Mark Waddingham via use-livecode < use-livecode@lists.runrev.com> wrote: > On 2018-04-03 10:28, David Bovill via use-livecode wrote: > > Arrays as first class citizens? Give them a passport! Arrays have > > rights > > too! > > > > Need to check if they can be passed as parameters in setprop handlers - > > as > > in “set the beautiful_Colour [spellingArray] of my card to light-grey” > > Heh - okay let me define what I mean by 'first-class citizen'... > > A 'thing' in a programming language is a 'first-class citizen' if it can > be placed in a variable, and further being then able to use that > variable to be able to access the functionality of 'thing' instead of > referencing 'thing' directly. i.e. 'thing' can be indirected. > > The above example confuses two things - the idea of being first-class, > and the ability to use a given type of value in a given context. SetProp > handlers are defined to take a string argument, as they are backed by a > LiveCode array (custom property set) if there is no handler to call (or > if messages are locked). So that's just a case of functionality which > has not been defined nor implemented. > > Perhaps the best example of a language feature which is nearly never > 'first-class' (as in, I don't believe there are any widely used general > programming languages which allow it) is types. e.g. You can't do things > like the following: > > put integer between 1 and 3 into tIntBetween1And3Type > put tMyString as tIntBetween1And3Type into tIntBetween1And3 > > Certainly you can approximate this in various languages - you *can* > build concrete instances of abstract base classes (i.e. ones with all > virtual methods) in C++ at runtime if you don't mind a bit of > bit-bashing; but you can't build a struct, or class which is used as a > value (i.e. not passed around as a pointer) which existing compiled code > can used. > > Warmest Regards, > > Mark. > > P.S. Looking at this another way - I'd perhaps characterize the above as > arrays are not 'complete' as values in LiveCode (as in: you can't use > arrays in all places where you can use strings, and would still make > sense), but I would say they were 'first-class'. I'd suggest > 'completeness as values' is a more stringent requirement than > 'first-class' - and is more that 'code has not been written to do that' > (incomplete), rather than the 'model of the language disallows any > notion of it being possible' (not first-class). > > P.P.S. You could rewrite your example as: > set the beautiful_Colour [ the arrayEncode of spellingArray ] of > this card to "light-grey" > Which suggests that arrays are actually 'complete' in LiveCode in the > sense suggested above - it is just you (as the coder) have to work a bit > harder to use them as such. > > -- > Mark Waddingham ~ m...@livecode.com ~ http://www.livecode.com/ > LiveCode: Everyone can create apps > > _______________________________________________ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
