473,836 Members | 1,455 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

Leap Yr regular expression

can someone give the regular expr. to validate leap yr like
02/29/2000,02/29/00

Thanks

Feb 17 '06
22 4465
On Sat, 18 Feb 2006 19:09:12 +0200, Lasse Reichstein Nielsen
<lr*@hotpop.com > wrote:
Sure, this example exploits a JS implementation, but it seems to be
similar between the browsers.


No exploit, it is behaving as expected, and should work in all compliant
implementations (except for years 0-99 where the year might be normalized
to 1900-1999).

I would change "== 2) ? 0 : 1" to just "!= 2".


Sorry, you mean "!=1" ?

Vladas
Feb 18 '06 #11
Vladas Saulis wrote:
[...] Lasse Reichstein Nielsen [...] wrote:
I would change "== 2) ? 0 : 1" to just "!= 2".


Sorry, you mean "!=1" ?


No, that would not be equivalent.

`(x == 2) ? 0 : 1' yields 0 (false) if x equals 2, 1 (true) otherwise.
`x != 1' yields true if x equals 2, false otherwise.

He means

`x != 2' which yields false if x equals 2, true otherwise.
PointedEars
Feb 18 '06 #12
On Sat, 18 Feb 2006 19:38:02 +0200, Thomas 'PointedEars' Lahn
<Po*********@we b.de> wrote:
Vladas Saulis wrote:
[...] Lasse Reichstein Nielsen [...] wrote:
I would change "== 2) ? 0 : 1" to just "!= 2".


Sorry, you mean "!=1" ?


No, that would not be equivalent.

`(x == 2) ? 0 : 1' yields 0 (false) if x equals 2, 1 (true) otherwise.
`x != 1' yields true if x equals 2, false otherwise.

He means

`x != 2' which yields false if x equals 2, true otherwise.
PointedEars


I think you all didn't understand the point:

When you create a date = YYYY.02.29 for a non-leap year, you get back a
YYYY.03.01.
And the getMonth() for the "March" is equal to 2 (for february = 1).

That's why I called it kinda an exploit (unexpected (for me) behaviour).

Vladas
Feb 18 '06 #13
On Sat, 18 Feb 2006 20:08:19 +0200, Vladas Saulis <vl****@prodata .lt>
wrote:
On Sat, 18 Feb 2006 19:38:02 +0200, Thomas 'PointedEars' Lahn
<Po*********@we b.de> wrote:
Vladas Saulis wrote:
[...] Lasse Reichstein Nielsen [...] wrote:
I would change "== 2) ? 0 : 1" to just "!= 2".

Sorry, you mean "!=1" ?


He he, I also missed the point... Sorry. He meant to replace *whole*
expression to "!=2"?
In this I agree.

Vladas
Feb 18 '06 #14
JRS: In article <11************ **********@f14g 2000cwb.googleg roups.com>
, dated Sat, 18 Feb 2006 02:49:18 remote, seen in
news:comp.lang. javascript, VK <sc**********@y ahoo.com> posted :
It is possible to imagine (but I have no idea if it indeed exists) that
by studying "1900", "1901" etc. *string sequences* one can discover a
pattern for strings representing a number divisible by four.
That's actually trivial to express, and the expression must be rather
like

JulianLeap = /([02468][048]|[13579][26])$/.test(Year)

// now check that year is divisible by four and return true or false
// also welcome to add any amount extra checks for the correct input:


Your presumed country, under the benevolent rule of His Majesty George
II, upgraded from that rule in 1752. Luke, ch10, v37, tail.

--
© John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v4.00 IE 4 ©
<URL:http://www.jibbering.c om/faq/> JL/RC: FAQ of news:comp.lang. javascript
<URL:http://www.merlyn.demo n.co.uk/js-index.htm> jscr maths, dates, sources.
<URL:http://www.merlyn.demo n.co.uk/> TP/BP/Delphi/jscr/&c, FAQ items, links.
Feb 18 '06 #15
JRS: In article <op.s458uhm28lq gld@eightpee>, dated Sat, 18 Feb 2006
15:52:55 remote, seen in news:comp.lang. javascript, Vladas Saulis
<vl****@prodata .lt> posted :
It's curious, but I found this working with ALL known (for me) browsers:

function isLeapYear(year ) {

return ((new Date(year, 1, 29, 0, 0).getMonth() == 2) ? 0 : 1);
}


A function of that nature should return a Boolean :

return new Date(year, 1, 29, 0, 0).getMonth() != 2

The following is preferable, though the programmer can do the addition :

return !new Date(year, 0, 366+31).getMont h()

--
© John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v4.00 MIME. ©
Web <URL:http://www.merlyn.demo n.co.uk/> - w. FAQish topics, links, acronyms
PAS EXE etc : <URL:http://www.merlyn.demo n.co.uk/programs/> - see 00index.htm
Dates - miscdate.htm moredate.htm js-dates.htm pas-time.htm critdate.htm etc.
Feb 18 '06 #16
On 18/02/2006 18:08, Vladas Saulis wrote:

[snip]
When you create a date = YYYY.02.29 for a non-leap year, you get back
a YYYY.03.01. And the getMonth() for the "March" is equal to 2 (for
february = 1).

That's why I called it kinda an exploit (unexpected (for me)
behaviour).


However, it /is/ expected behaviour. The Date object is well-known for
handling out-of-range values by adjusting adjacent fields. It does this
by design.

Mike

--
Michael Winter
Prefix subject with [News] before replying by e-mail.
Feb 19 '06 #17
JRS: In article <ko************ ******@text.new s.blueyonder.co .uk>,
dated Sun, 19 Feb 2006 00:57:52 remote, seen in
news:comp.lang. javascript, Michael Winter <m.******@bluey onder.co.uk>
posted :
On 18/02/2006 18:08, Vladas Saulis wrote:

[snip]
When you create a date = YYYY.02.29 for a non-leap year, you get back
a YYYY.03.01. And the getMonth() for the "March" is equal to 2 (for
february = 1).

That's why I called it kinda an exploit (unexpected (for me)
behaviour).


However, it /is/ expected behaviour. The Date object is well-known for
handling out-of-range values by adjusting adjacent fields. It does this
by design.


For those who injudiciously put VBscript on Web pages, or who more
sagaciously use VBscript in WSH :

Functions DateSerial and TimeSerial have corresponding behaviour.

--
© John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v4.00 MIME. ©
Web <URL:http://www.merlyn.demo n.co.uk/> - w. FAQish topics, links, acronyms
PAS EXE etc : <URL:http://www.merlyn.demo n.co.uk/programs/> - see 00index.htm
Dates - miscdate.htm moredate.htm js-dates.htm pas-time.htm critdate.htm etc.
Feb 19 '06 #18
Dr John Stockton said the following on 2/19/2006 3:04 PM:
JRS: In article <ko************ ******@text.new s.blueyonder.co .uk>,
dated Sun, 19 Feb 2006 00:57:52 remote, seen in
news:comp.lang. javascript, Michael Winter <m.******@bluey onder.co.uk>
posted :
On 18/02/2006 18:08, Vladas Saulis wrote:

[snip]
When you create a date = YYYY.02.29 for a non-leap year, you get back
a YYYY.03.01. And the getMonth() for the "March" is equal to 2 (for
february = 1).

That's why I called it kinda an exploit (unexpected (for me)
behaviour). However, it /is/ expected behaviour. The Date object is well-known for
handling out-of-range values by adjusting adjacent fields. It does this
by design.


For those who injudiciously put VBscript on Web pages,


There is nothing "injudiciou s" about putting VBScript on Web pages.

It's wise if you know when, its ignorant if you don't.
or who more sagaciously use VBscript in WSH :


Sesquipedalian behavior is a sign of ignorance, not intelligence.

--
Randy
comp.lang.javas cript FAQ - http://jibbering.com/faq & newsgroup weekly
Javascript Best Practices - http://www.JavascriptToolbox.com/bestpractices/
Feb 20 '06 #19
On Sun, 19 Feb 2006 02:57:52 +0200, Michael Winter
<m.******@bluey onder.co.uk> wrote:
On 18/02/2006 18:08, Vladas Saulis wrote:

[snip]
When you create a date = YYYY.02.29 for a non-leap year, you get back
a YYYY.03.01. And the getMonth() for the "March" is equal to 2 (for
february = 1).
That's why I called it kinda an exploit (unexpected (for me)
behaviour).


However, it /is/ expected behaviour. The Date object is well-known for
handling out-of-range values by adjusting adjacent fields. It does this
by design.


Following this logic, then the date = YYYY.MM.00 should return the last
day of the previous month.
Am I right? (I have no time to test :).

Vladas
Feb 20 '06 #20

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

1
4191
by: Kenneth McDonald | last post by:
I'm working on the 0.8 release of my 'rex' module, and would appreciate feedback, suggestions, and criticism as I work towards finalizing the API and feature sets. rex is a module intended to make regular expressions easier to create and use (and in my experience as a regular expression user, it makes them MUCH easier to create and use.) I'm still working on formal documentation, and in any case, such documentation isn't necessarily the...
4
5178
by: Buddy | last post by:
Can someone please show me how to create a regular expression to do the following My text is set to MyColumn{1, 100} Test I want a regular expression that sets the text to the following testMyColumn{1, 100}Test Basically I want the regular expression to add the word test infront of the
4
3237
by: Neri | last post by:
Some document processing program I write has to deal with documents that have headers and footers that are unnecessary for the main processing part. Therefore, I'm using a regular expression to go over each document, find out if it contains a header and/or a footer and extract only the main content part. The headers and the footers have no specific format and I have to detect and remove them using a list of strings that may appear as...
11
5400
by: Dimitris Georgakopuolos | last post by:
Hello, I have a text file that I load up to a string. The text includes certain expression like {firstName} or {userName} that I want to match and then replace with a new expression. However, I want to use the text included within the brackets to do a lookup so that I can replace the expression with the new text. For example:
3
3225
by: James D. Marshall | last post by:
The issue at hand, I believe is my comprehension of using regular expression, specially to assist in replacing the expression with other text. using regular expression (\s*) my understanding is that this will one or more occurrences to replace all the white space between with a comma. This search ElseIf InStr(1, indivline, "$") Then insert a replace statement that uses the regular expression to find and replace all the white space...
7
3836
by: Billa | last post by:
Hi, I am replaceing a big string using different regular expressions (see some example at the end of the message). The problem is whenever I apply a "replace" it makes a new copy of string and I want to avoid that. My question here is if there is a way to pass either a memory stream or array of "find", "replace" expressions or any other way to avoid multiple copies of a string. Any help will be highly appreciated
25
5185
by: Mike | last post by:
I have a regular expression (^(.+)(?=\s*).*\1 ) that results in matches. I would like to get what the actual regular expression is. In other words, when I apply ^(.+)(?=\s*).*\1 to " HEART (CONDUCTION DEFECT) 37.33/2 HEART (CONDUCTION DEFECT) WITH CATHETER 37.34/2 " the expression is "HEART (CONDUCTION DEFECT)". How do I gain access to the expression (not the matches) at runtime? Thanks, Mike
1
4391
by: Allan Ebdrup | last post by:
I have a dynamic list of regular expressions, the expressions don't change very often but they can change. And I have a single string that I want to match the regular expressions against and find the first regular expression that matches the string. I've gor the regular expressions ordered so that the highest priority is first (if two or more regular expressions match the string I want the first one returned) The code that does this has...
1
3413
by: NvrBst | last post by:
I want to use the .replace() method with the regular expression /^ %VAR % =,($|&)/. The following DOESN'T replace the "^default.aspx=,($|&)" regular expression with "": --------------------------------- myStringVar = myStringVar.replace("^" + iName + "=,($|&)", ""); --------------------------------- The following DOES replace it though: --------------------------------- var match = myStringVar.match("^" + iName + "=,($|&)");
0
9825
marktang
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main usage, and What is the difference between ONU and Router. Let’s take a closer look ! Part I. Meaning of...
0
9673
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
0
10859
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed. This is as boiled down as I can make it. Here is my compilation command: g++-12 -std=c++20 -Wnarrowing bit_field.cpp Here is the code in...
1
10602
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
0
9388
agi2029
by: agi2029 | last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own.... Now, this would greatly impact the work of software developers. The idea...
0
6984
by: conductexam | last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one. At the time of converting from word file to html my equations which are in the word document file was convert into image. Globals.ThisAddIn.Application.ActiveDocument.Select();...
0
5829
by: adsilva | last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
2
4023
muto222
by: muto222 | last post by:
How can i add a mobile payment intergratation into php mysql website.
3
3116
bsmnconsultancy
by: bsmnconsultancy | last post by:
In today's digital era, a well-designed website is crucial for businesses looking to succeed. Whether you're a small business owner or a large corporation in Toronto, having a strong online presence can significantly impact your brand's success. BSMN Consultancy, a leader in Website Development in Toronto offers valuable insights into creating effective websites that not only look great but also perform exceptionally well. In this comprehensive...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.