1. "eval()" commands/crash callbacks/ect. for Euphoria 2.5?
Some of the following is missing from Euphoria and would be very
helpful to me and many other programmers. I would like to see this in
Eu 2.5. Please take these into consideration.
"eval()" commands:
I would really like to see a way to do an "eval()" type command.
Many other languages have something like this.
eval(sequence eval_commands,integer global_type,integer crash)
eval_commands is a sequence of commands
global_type is:
0-No routines/varibles (even global) exist in main program
1-Only routines/varibles declared as global exist in main program
2-All routines/varibles exist in main program
if crash is true, if it encounters an error (like 1/0) than the
program dies with (or a crash routine, see below) ex.err, otherwise, it
returns an error
code(like 5 for divide by 0,see below)
Example:
integer a,global_type
sequence eval_commands
eval_commands="
include incl_file.e--should allow including(This could be used
--instead of complex "dynamic includeing" libraries)
if a then
?a
end if"
a=7
var_type=1
?eval(eval_commands,global_type,0)
Displays:
7(value of a)
0(eval encountered no errors)
____________________________________________________________
Crash callback
A way to setup a callback function would allow programs to save user
data before exiting
with ex.err
set_crash(integer routine_id)
routine_id is the routine id of the function
it calls the function with an error code(like 5 for divide by 0),
a sequence with info about the error(like a line #, invalid subscript,
ect.)
and a text string with the complete text error message(
"test.ex:3
attempt to divide by 0")
if the function returns -1, ignore the error
Example:
function oncrash(integer err_code,sequence info,sequence msg)
if err_code=34 then--this error can be ignored in this program
return -1
end if
save_all_important_data()
return 0
end function
set_crash(routine_id("oncrash"))
_________________________________________________
routine_id() for variables
I would like to see a varible_id systym (like routine id)
example:
integer a,a_id a=3
a_id=var_id("a")
?get_var(a_id)
--displays 3
set_var(a_id,4)
--a now is 4
_________________________________________________________
and mayby a way to see if a var exists/is set
Example:
integer a,b a=1
?is_var_set("a")
--1 because a is set
?is_var_set("b")
--0 because b exists, but is not set
?is_var_set("c")
-- -1 because c doesn't exist
____________________________________________________________
2. Re: "eval()" commands/crash callbacks/ect. for Euphoria 2.5?
----- Original Message -----
From: "CoJaBo" <cojabo at suscom.net>
To: <EUforum at topica.com>
Subject: "eval()" commands/crash callbacks/ect. for Euphoria 2.5?
> In the first example, even if it did include the file, when it is bound
> the line 'eval_commands = include incl_file.e' whould look like
> 'eval_commands = (The entire file as a sequence or something).
Personaly I like the current include method. all include file
routines are declared at top level.
In the second example, useing poke, peek and call can do the same thing.
However I agree on the last example but I would like to see it more like
this.
n.b. Where 'exist' is a low level machine proc.
integer a
-- lots a code.
-- more code.
-- for some reason 'a' has still not been declared.
if exist(a) then
-- do something
end if -- In this case 'exist' would return 'False'.
I think a command like this could be used to catch
unexpected runtime errors in AI Intelligence programming,
unassighned variables etc.. and the boolen returned from
'exist' could be pased to a funtion to deal with the runtime error.
> CoJaBo wrote:
> Some of the following is missing from Euphoria and would be very
> helpful to me and many other programmers. I would like to see this in
> Eu 2.5. Please take these into consideration.
>
> <Snip>
> eval_commands="
> include incl_file.e--should allow including(This could be used
> --instead of complex "dynamic includeing" libraries)
> if a then
> ?a
> end if"
>
> a=7
> var_type=1
>
> ?eval(eval_commands,global_type,0)
> Displays:
> 7(value of a)
> 0(eval encountered no errors)
>
>
> routine_id() for variables
> I would like to see a varible_id systym (like routine id)
> example:
> integer a,a_id a=3
> a_id=var_id("a")
> ?get_var(a_id)
> --displays 3
> set_var(a_id,4)
> --a now is 4
> --1 because a is set
>
> ?is_var_set("b")
> --0 because b exists, but is not set
>
> ?is_var_set("c")
> -- -1 because c doesn't exist
>
>
>
> TOPICA - Start your own email discussion group. FREE!
>
>
> --
> Incoming mail is certified Virus Free.
> Checked by AVG anti-virus system (http://www.grisoft.com).
> Version: 6.0.558 / Virus Database: 350 - Release Date: 2/01/04
>
---
--
3. Re: "eval()" commands/crash callbacks/ect. for Euphoria 2.5?
Kat wrote:
>>Almost all other languages I've used had an "eval()" command, this would=
>>=20
>>be very useful in Euphoria.
>>
>>
>I agreed=20 with=20 you!!=20 Please=45 explain=60 this=50to RDS!!=98
>=74
>=-3456.2
>Kat=65
>
>
LOL, Kat. You so silly...
