Ayende @ Rahien

Hi!
My name is Oren Eini
Founder of Hibernating Rhinos LTD and RavenDB.
You can reach me by email or phone:

ayende@ayende.com

+972 52-548-6969

, @ Q a b j

Posts: 6,609 | Comments: 48,322

filter by tags archive

architecture (305) rss
bugs (364) rss
challanges (78) rss
community (200) rss
databases (313) rss
design (614) rss
development (380) rss
ef prof (55) rss
hibernating rhinos (42) rss
hibernating-practices (21) rss
humor (166) rss
macto (35) rss
miscellaneous (576) rss
nh prof (154) rss
performance (302) rss
programming (894) rss
raven (975) rss
reddit (25) rss
reviews (161) rss
wtf?! (54) rss

2018
- April (14)
- March (23)
- February (19)
- January (23)
2017
- December (21)
- November (24)
- October (22)
- September (21)
- August (23)
- July (21)
- June (24)
- May (21)
- April (21)
- March (23)
- February (20)
- January (23)
2016
- December (17)
- November (18)
- October (22)
- September (18)
- August (23)
- July (22)
- June (17)
- May (24)
- April (16)
- March (16)
- February (21)
- January (21)
2015
- December (5)
- November (10)
- October (9)
- September (17)
- August (20)
- July (17)
- June (4)
- May (12)
- April (9)
- March (8)
- February (25)
- January (17)
2014
- December (22)
- November (19)
- October (21)
- September (37)
- August (24)
- July (23)
- June (13)
- May (19)
- April (24)
- March (23)
- February (21)
- January (24)
2013
- December (23)
- November (29)
- October (27)
- September (26)
- August (24)
- July (24)
- June (23)
- May (25)
- April (26)
- March (24)
- February (24)
- January (21)
2012
- December (19)
- November (22)
- October (27)
- September (24)
- August (30)
- July (23)
- June (25)
- May (23)
- April (25)
- March (25)
- February (28)
- January (24)
2011
- December (17)
- November (14)
- October (24)
- September (28)
- August (27)
- July (30)
- June (19)
- May (16)
- April (30)
- March (23)
- February (11)
- January (26)
2010
- December (29)
- November (28)
- October (35)
- September (33)
- August (44)
- July (17)
- June (20)
- May (53)
- April (29)
- March (35)
- February (33)
- January (36)
2009
- December (37)
- November (35)
- October (53)
- September (60)
- August (66)
- July (29)
- June (24)
- May (52)
- April (63)
- March (35)
- February (53)
- January (50)
2008
- December (58)
- November (65)
- October (46)
- September (48)
- August (96)
- July (87)
- June (45)
- May (51)
- April (52)
- March (70)
- February (43)
- January (49)
2007
- December (100)
- November (52)
- October (109)
- September (68)
- August (80)
- July (56)
- June (150)
- May (115)
- April (73)
- March (124)
- February (102)
- January (68)
2006
- December (95)
- November (53)
- October (120)
- September (57)
- August (88)
- July (54)
- June (103)
- May (89)
- April (84)
- March (143)
- February (78)
- January (64)
2005
- December (70)
- November (97)
- October (91)
- September (61)
- August (74)
- July (92)
- June (100)
- May (53)
- April (42)
- March (41)
- February (84)
- January (31)
2004
- December (49)
- November (26)
- October (26)
- September (6)
- April (10)

Jul 02 2013

Spot the bug…

time to read 1 min | 39 words

Do you see it? It took me ages to find it.

aTweet bshare jshare 11 comments

Tags:

bugs

Comments

02 Jul 2013
09:09 AM

Igal Tabachnik

Yay scoping braces!

02 Jul 2013
09:10 AM

Fredrik

Ha ha, it's quite subtle, but so obvious once you spot it.

02 Jul 2013
09:11 AM

Sebastian

I think there is something 'else' missing ;-)

02 Jul 2013
09:15 AM

Ramon Smits

Missing else?

02 Jul 2013
09:26 AM

Sam

LOL, I didn't saw it either

02 Jul 2013
09:46 AM

Marc Brooks

Not to mention the sheer lunacy of mid not being related to target in any discernable way. Ugh.

(oh, yeah, and missing else)

02 Jul 2013
10:00 AM

P.Czatrowski

Apart from missing else, what about arithmetic overflow?

I would change the line: var mid = (left + right + 1) / 2;

to this: var mid = left + (right - left + 1) / 2;

You still get the same result, but it's a little bit safer for higher values.

02 Jul 2013
10:08 AM

tobi

The bug aside, I'd use checked((left + right + 1) / 2).

03 Jul 2013
08:25 AM

Roman Boiko

Another potential problem: behavior of comparator might be not aligned with subtraction, so that

_comparator.Compare(mid-1, mid) >=0

05 Jul 2013
07:48 AM

Alex

This is really a tricky problem to spot. :) Everyone is focused on the code inside the brackets and the missing "else" is not being observed very fast.

12 Jul 2013
09:18 AM

Adam Fridental

Sorry to dissapoint, took me a second.

Anyway, I don't belive in scoping braces when they contain 1 line, it's not safer and not easier to read.. just redundant.

Comment preview

Comments have been closed on this topic.

Markdown turns plain text formatting into fancy HTML formatting.

Phrase Emphasis

*italic*   **bold**
_italic_   __bold__

Links

Inline:

An [example](http://url.com/ "Title")

Reference-style labels (titles are optional):

An [example][id]. Then, anywhere
else in the doc, define the link:
  [id]: http://example.com/  "Title"

Images

Inline (titles are optional):

![alt text](/path/img.jpg "Title")

Reference-style:

![alt text][id]
[id]: /url/to/img.jpg "Title"

Headers

Setext-style:

Header 1
========
Header 2
--------

atx-style (closing #'s are optional):

# Header 1 #
## Header 2 ##
###### Header 6

Lists

Ordered, without paragraphs:

1.  Foo
2.  Bar

Unordered, with paragraphs:

*   A list item.
    With multiple paragraphs.
*   Bar

You can nest them:

*   Abacus
    * answer
*   Bubbles
    1.  bunk
    2.  bupkis
        * BELITTLER
    3. burper
*   Cunning

Blockquotes

> Email-style angle brackets
> are used for blockquotes.
> > And, they can be nested.
> #### Headers in blockquotes
> 
> * You can quote a list.
> * Etc.

Horizontal Rules

Three or more dashes or asterisks:

---
* * *
- - - -

Manual Line Breaks

End a line with two or more spaces:

Roses are red,   
Violets are blue.

Fenced Code Blocks

Code blocks delimited by 3 or more backticks or tildas:

```
This is a preformatted
code block
```

Header IDs

Set the id of headings with {#<id>} at end of heading line:

## My Heading {#myheading}

Tables

Fruit    |Color
---------|----------
Apples   |Red
Pears	 |Green
Bananas  |Yellow

Definition Lists

Term 1
: Definition 1
Term 2
: Definition 2

Footnotes

Body text with a footnote [^1]
[^1]: Footnote text here

Abbreviations

MDD <- will have title
*[MDD]: MarkdownDeep

FUTURE POSTS

No future posts left, oh my!

RECENT SERIES

Inside RavenDB 4.0 (8):
24 Apr 2018 - Chapter 17 is done
RavenDB Security Report (5):
06 Apr 2018 - Collision in Certificate Serial Numbers
Challenge (52):
03 Apr 2018 - The invisible concurrency bug–Answer
RavenDB Security Review (5):
27 Mar 2018 - Non-Constant Time Secret Comparison
Properly getting into jail (13):
19 Mar 2018 - The almighty document

View all series

Syndication

Main feed
Comments feed

Ayende @ Rahien

Ayende @ Rahien

Spot the bug…

Comments

Comment preview

Markdown formatting

Phrase Emphasis

Links

Images

Headers

Lists

Blockquotes

Horizontal Rules

Manual Line Breaks

Fenced Code Blocks

Header IDs

Tables

Definition Lists

Footnotes

Abbreviations

FUTURE POSTS

RECENT SERIES

RECENT COMMENTS

Syndication