1. compare , zero indexing (Re: mainly syntax)
David Cuny wrote:
> compare() vs. "=" is just trouble waiting to happen. I assume that the
> reason that Euphoria uses compare is so that the "=" operator can be
> optimized to handle numeric values.
No, I don't think so. Compare() returns three values: less than,
equal, greater than. = only two: equal, unequal.
What threw me off is that "if x=y" reports an error
when x and y are strings, and that compare() returns
-1, 0, or 1. Me, simple-minded linguist that I am,
I have written myself compare functions in Pascal before,
but I had them return '<', '=', and '>'!
> [Zero Indexing]
> The rest of the programming world starts counting with zero
Except Pascal, ALGOL, Simula, Ada, Modula, and, I imagine, others
I do not know about, which start counting from whatever you tell
them. I am quite happy with counting from 1 in Euphoria, I am
not a Mayan, you know (they counted the days of the month
from zero).
> At a minimum, we need a mechanism that can be called to save the user's
> precious data before the program shuts down. Preferably, I should be able
> to place a routine id in a variable:
> onError = routine_id( "save_user_data" )
I agree there. I had been looking for something like that in the
reference library and the manual, and was surprised not to find
anything. I thought it was myopic me.
2. Re: compare , zero indexing (Re: mainly syntax)
> No, I don't think so. Compare() returns three values: less than,
> equal, greater than. = only two: equal, unequal.
>
> What threw me off is that "if x=y" reports an error
> when x and y are strings, and that compare() returns
> -1, 0, or 1. Me, simple-minded linguist that I am,
> I have written myself compare functions in Pascal before,
> but I had them return '<', '=', and '>'!
Yay, another linguist (syntactician, actually 
! Anyway, compare() or
the equivalent in a lot of languages also returns -1, 0 and 1. Perl
uses the 'cmp' or '<=>' operators; and most languages, when they ask for a sort
function to sort an array through, expect it to return -1, 0 or 1 (Perl,
uLPC/Pike, LPC do this, probably others).
> Except Pascal, ALGOL, Simula, Ada, Modula, and, I imagine, others
> I do not know about, which start counting from whatever you tell
> them. I am quite happy with counting from 1 in Euphoria, I am
> not a Mayan, you know (they counted the days of the month
> from zero).
Actually, BASIC doesn't have to, surprisingly. At least on C64s, you can
start assigning to arrays at element 0, although it's uncommon. I would
expect most Microsoft 8-bit BASICs, like Applesoft and Atari Microsoft BASIC,
did the same.
> I agree there. I had been looking for something like that in the
> reference library and the manual, and was surprised not to find
> anything. I thought it was myopic me.
Perl has a whole raft of signal handling features. You can have a __DIE__
trap to hook fatal errors -- even compile-time ones (!), and while DOS
Euphoria doesn't have much call for trapping SIGALRM, it might in a
Unix version )))).
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