function call

[Philip WATTS]

Can anyone help me with the following code. What ever entry I make for
variable "year" the function excecuted is "checkleapd ays" and not
"checkdays" . I know from the alert that leap works out correctly, ie 0 on a
leap year and non-zero otherwise, but always the "checkleapd ays" function is
called.

Any advise?

Code

var leap=year % 4
alert(leap)
if (leap=0){
checkleapdays(d ay,month)
}
else{
checkdays(day,m onth)}

[Lasse Reichstein Nielsen]

Re: function call

"Philip WATTS" <PRWATTS@syring a.freeserve.co. uk> writes:
[color=blue]
> Can anyone help me with the following code. What ever entry I make for
> variable "year" the function excecuted is "checkleapd ays" and not
> "checkdays" .[/color]

Are you sure? I would have expected it to always call "checkdays" .
[color=blue]
> if (leap=0){[/color]

Comparison is the "==" operator. You are *assigning* 0 to the variable
"leap". The value of an assignment is the assigned value, so this is
equivalent to
if (0)
which is again equivalent to
if (false)
That is why I expect the "else" branch to be taken every time.

/L
--
Lasse Reichstein Nielsen - lrn@hotpop.com
Art D'HTML: <URL:http://www.infimum.dk/HTML/randomArtSplit. html>
'Faith without judgement merely degrades the spirit divine.'

[Hywel Jenkins]

Re: function call

In article <blscuf$iai$1@n ews7.svr.pol.co .uk>,
PRWATTS@syringa .freeserve.co.u k says...[color=blue]
> Can anyone help me with the following code. What ever entry I make for
> variable "year" the function excecuted is "checkleapd ays" and not
> "checkdays" . I know from the alert that leap works out correctly, ie 0 on a
> leap year and non-zero otherwise, but always the "checkleapd ays" function is
> called.
>
> Any advise?
>
> Code
>
> var leap=year % 4
> alert(leap)
> if (leap=0){
> checkleapdays(d ay,month)
> }
> else{
> checkdays(day,m onth)}[/color]

For checking leap years, that code is slightly out. For example, 1900
is divisible by 4, but wasn't a leap year.

--
Hywel I do not eat quiche

http://hyweljenkins.co.uk/

http://hyweljenkins.co.uk/mfaq.php

[Dr John Stockton]

Re: function call

JRS: In article <blscuf$iai$1@n ews7.svr.pol.co .uk>, seen in
news:comp.lang. javascript, Philip WATTS <PRWATTS@syring a.freeserve.co. uk[color=blue]
> posted at Mon, 6 Oct 2003 19:40:14 :-
>Can anyone help me with the following code. What ever entry I make for
>variable "year" the function excecuted is "checkleapd ays" and not
>"checkdays" . I know from the alert that leap works out correctly, ie 0 on a
>leap year and non-zero otherwise, but always the "checkleapd ays" function is
>called.
>
>Any advise?
>
>Code
>
>var leap=year % 4
>alert(leap)
>if (leap=0){
>checkleapdays( day,month)
>}
>else{
>checkdays(day, month)}[/color]

(leap==0).

But you do not need to write code like that, unless you ate using the
Julian Calendar or some other non-Gregorian one; there is always a
better way of doing it, employing the power of the Date Object.

The following, for example, should determine whether a YMD triple
represents a valid date on the proleptic astronomical Gregorian
calendar, up to AD 275760-09-13. It may only be guaranteed after 1970.
It will be wrong, in MSIE4 at least, for the Year Zero, since new Date
there takes a Y in 0..99 to be in 1900..1999. Otherwise it is probably
OK back to -271821 April 21.


function ValidDate(y, m, d) { // m = 0..11 ; y m d integers
with (new Date(y, m, d))
return ((getMonth()==m ) && (getDate()==d)) /* was y, m */ }



Read the FAQ; see below.

--
© John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v4.00 IE 4 ©
<URL:http://jibbering.com/faq/> Jim Ley's FAQ for news:comp.lang. javascript
<URL:http://www.merlyn.demo n.co.uk/js-index.htm> JS maths, dates, sources.
<URL:http://www.merlyn.demo n.co.uk/> TP/BP/Delphi/JS/&c., FAQ topics, links.