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16h
comment Should users be allowed to use any special character they want when creating a password?
...but would seem very odd to a mathematician.)
16h
comment Should users be allowed to use any special character they want when creating a password?
@oefe: When keyboards are set to input Latin alphabet (as opposed to Greek, Cyrillic, etc.), knowing that a key generates a character that looks like y is a pretty strong indication that the key is generating code point 0x00059, even if the key is positioned to the left of "X" on the bottom row and is labeled "Z". It's far less clear whether e.g. a Mathemetician's keyboard layout which includes a "א" key should have it generate a single character, or have it also generate marks to control writing direction (having aleph-1234 appear as "א1234" may seem normal to someone writing Hebrew...
18h
comment How easy to read are small caps vs lower case?
The ability to distinguish upper and lowercase letters can help parsing, and in some cases may be semantically required. In cases where space or technical constraints would preclude the use of descenders, small caps may make it possible to preserve the uppercase/lowercase distinction while being less ugly than descender-less gjpqy. This may work well in cases which use mostly allcaps but put use lowercase to disambiguate a few things [though interestingly in many such cases the lowercase letters in question would lack descenders].
20h
comment Should users be allowed to use any special character they want when creating a password?
I think the gap in historical renderings of ASCII character 0x7C is there to ensure that when rendered with a 7-pin printer it would not be confusable with "I", "l", or "1". Are you saying that Android devices don't have a key for code point 0x7C but instead have one for some other code point that renders as "¦", or that Android's fonts include a gap in their rendering of code point 0x7C? If the former, what do programmers on Android use for the "or" operator?
20h
comment Should users be allowed to use any special character they want when creating a password?
@CodesInChaos: I find it somewhat surprising that international versions of Windows would change the meanings of code points, especially 32-126; a more interesting question would relate to the behavior of files which would appear like they could either be ASCII or UTF-8. If 0x5C is a Won symbol, is there any character which is semantically equivalent to a 0x5C backslash? As for normalization, that would suffice if one could guarantee that anything that normalizes the password prior to hashing will always treat any given string the same way, but I don't think it's easy to guarantee that.
1d
awarded  Nice Answer
1d
comment Should users be allowed to use any special character they want when creating a password?
@neminem: Unfortunately, such an approach doesn't really work for passwords. If a password contains eight characters, each of which might appear in two different forms, the only way to find out if it is equivalent to a particular hashed password is to try hashing all 256 combinations of characters to see if any of them work. Nasty.
1d
comment Should users be allowed to use any special character they want when creating a password?
@neminem: Unicode has a lot of tricky rules and edge cases. In the old days, code could be character-set agnostic for any sequence of bytes that didn't contain nulls, but that's no longer the case. For usages other than passwords, the fact that a database sometimes represents "mañana" as six code points and sometimes represents it as seven may be an annoyance, but it can be resolved by having a search for "mañana" look for both forms. Even if a string has many characters that could appear in multiple forms, it may be possible to search for all forms simultaneously.
1d
comment Should users be allowed to use any special character they want when creating a password?
@sapi: If one wishes to safely allow non-ASCII characters, one approach would be to say that if a password contains any non-ASCII characters or unbalanced ASCII-brace characters, all non-ASCII characters and any ASCII brace characters will be replaced by their character code, enclosed in braces before hashing. Such behavior would generally be transparent to the user, but would provide a means by which a user whose password contained e.g. the codepoint sequence 0030B+00065 could enter it, even if his system would normally replace it with 000EB.
1d
comment Should users be allowed to use any special character they want when creating a password?
@DaveAlger: Although code could accept most Unicode characters without difficulty, some really shouldn't be, and there's no easy way to determine which ones those are. Even if code had a list of 70,000 characters which were known to be problem-free, a list of 94 permissible characters will probably be easier for users to work with than would be a list of 70,000.
1d
answered Should users be allowed to use any special character they want when creating a password?
Jan
24
answered Is there a problem with using black text on white backgrounds?
Jan
23
comment What cues can I use to nudge users away from setting extreme values on a slider?
Oftentimes I find running sliders to the extremes to be a useful way of evaluating certain things about a picture; cranking both brightness and contrast up to maximum, for example, is often an easy way to see how much detail the "black" parts of a picture contain. Perhaps users aren't concerned about the image aesthetics, but are trying to make judgments about something in it?
Jan
20
answered Why are calculator screen digits right-aligned?
Jan
17
awarded  Yearling
Jan
14
comment Why did the mouse beat the light pen, paddle, and other pointing devices?
@Almo: Some mouse drivers work better than others; someone who uses a decent mouse/driver can generally point to an arbitrary spot pretty quickly with only one or two motions.
Jan
13
answered Why do idle elevators close the doors?
Jan
12
awarded  Caucus
Dec
19
comment Asirra or Captcha?
Asirra will accept a user who achieves two near-perfect scores; it does not require perfection.
Nov
27
comment Confirm vs. Verify: Is there a difference?
@TripeHound: The service would, for purposes of verifying the user's email address, ask the user to confirm that the address is correct. Using the term "verify" for both would be more accurate than using "confirm" for both; using "verify" for the service's actions and "confirm" for the user action may be more accurate, but might possibly be confusing.