OpenEuphoria

Re: Enum?

• Posted by Jason Gade <jaygade at yah?o.?om> May 15, 2008
• 754 views

Jeremy Cowgar wrote:
> 
> I do this all the time and I know others do because I see in it code
> everywhere.
> Here are some examples, some of which you will recognize:
> 
> }}}
<eucode>
> constant FILE_NO = 1,           -- file number
> 	 LINE_NO = 2,           -- local line number
> 	 FILE_PTR = 3,          -- open file number 
> 	 FILE_START_SYM = 4,    -- symbol before start of file
> 	 OP_WARNING = 5,        -- save/restore with/without options
> 	 OP_TRACE = 6,          
> 	 OP_TYPE_CHECK = 7,
> 	 OP_PROFILE_TIME = 8,
> 	 OP_PROFILE_STATEMENT = 9,
>          OP_DEFINES = 10        -- ifdef defines
> 
> global constant GET_SUCCESS = 0,
> 		GET_EOF = -1,
> 		GET_FAIL = 1,
> 		GET_NOTHING = -2
> 
> global constant 
> 	D_NAME = 1,
> 	D_ATTRIBUTES = 2,
> 	D_SIZE = 3,
> 	D_YEAR = 4,
> 	D_MONTH = 5,
> 	D_DAY = 6,
> 	D_HOUR = 7,
> 	D_MINUTE = 8,
> 	D_SECOND = 9
> </eucode>
{{{

> 
> Etc... This is fine, but what if you want to add a new element and not at the
> end? I am sure we've all done it. Well, I borrowed a good thing from other
> languages
> called an enum (enumeration)... I've done the code already but have not
> committed.
> What do you think?
> 
> }}}
<eucode>
> global enum D_NAME, D_ATTRIBUTES, D_SIZE, ...
> global enum PERSON_NAME, PERSON_AGE=5, PERSON_DOB, PERSON_EMAIL
> 
> printf(1, "name=%d, attributes=%d, size=%d\n", {
>     D_NAME, D_ATTRIBUTES, D_SIZE})
> printf(1, "person_name=%d, age=%d, dob=%d, email=%d\n", {
>     PERSON_NAME, PERSON_AGE, PERSON_DOB, PERSON_EMAIL})
> 
> -- name=1, attributes=2, size=3
> -- person_name=1, age=5, dob=6, email=7
> </eucode>
{{{

> 
> An enum is not a new type, it emits a constant. They can be local or global.
> I think it has a lot of benefit but wanted to get community input.
> 
> --
> Jeremy Cowgar
> <a href="http://jeremy.cowgar.com">http://jeremy.cowgar.com</a>

Yes, I think with the ubiquity of sequences and how they are used to simulate
structures sometimes, enumerated constants would be a welcome addition.

--
A complex system that works is invariably found to have evolved from a simple
system that works.
--John Gall's 15th law of Systemantics.

"Premature optimization is the root of all evil in programming."
--C.A.R. Hoare

j.