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#10021 closed bug (fixed)

Opened August 11, 2011 04:13AM UTC

Closed August 25, 2011 07:23PM UTC

Last modified August 26, 2011 02:45PM UTC

Can't add negative numbers using the relative-value syntax with .css() and .animate()

Reported by: Owned by: dmethvin
Priority: low Milestone: 1.6.3
Component: css Version: 1.6.2
Keywords: Cc:
Blocked by: Blocking:

When I use the relative-value syntax in my .css() and .animate(), I can't add negative numbers like so:


This comes up when you're building up the value using string concatenation and you don't know whether the value is positive of negative:


Here's a jsFiddle which highlights the problem:

Attachments (0)
Change History (7)

Changed August 16, 2011 05:42AM UTC by addyosmani comment:1

component: unfiledcss
priority: undecidedlow
resolution: → wontfix
status: newclosed

Thanks for submitting a ticket to the jQuery bug tracker. I've never actually seen anyone use relative-value syntax in the way described for negative numbers (ie. +=-1).

Why not simply use the (more common) negative equivalent of +=1 (ie. -=1?). If there is an uncertainty about where the value used in your string concatenation example is positive or negative, there are many ways you can use to test this.

For example, if the value passed is a string (with or without units) var myOperator = (parseInt(value) <0)? '-=' : '+='; would allow you to get the correct operator to use and you can then simply use $('#foo').css('margin-left', myOperator +value); as per your example.

Changed August 16, 2011 05:46AM UTC by anonymous comment:2

You're right, nobody would write out +=-1 by hand, but my point is, users shouldn't have to write out the tertiary operator by hand when what they're trying to say is perfectly valid. That kind of conditional code is messy and annoying to write. Besides, adding a negative number is a valid mathematical expression :)

Changed August 16, 2011 07:29PM UTC by dmethvin comment:3

resolution: wontfix
status: closedreopened

I think this may be a very easy fix, just add the minus sign to the rfxnum regexp in effects.js. The code in css.js needs a bit more tweaking to code but it shouldn't be much.

Changed August 16, 2011 07:30PM UTC by dmethvin comment:4

milestone: None1.6.3
owner: → dmethvin
status: reopenedassigned

Changed August 16, 2011 09:55PM UTC by dmethvin comment:5

Animation already works, css does not.

Changed August 25, 2011 07:23PM UTC by Dave Methvin comment:6

resolution: → fixed
status: assignedclosed

Merge pull request #464 from dmethvin/fix-10021-relative-negative-values

Fixes #10021. Allow negative relative values for .css()

Changeset: 3ba72f991dccbae6020c23d6f7a65435f4ca6f03

Changed August 26, 2011 02:45PM UTC by rwldrn comment:7

Landing pull request 476. Fix lint complaints about unescaped -. Follow up to #10021 Fixes #10021.

More Details:

Changeset: 3589a53de98c63a528855755492875318ed0136c