Beefy Boxes and Bandwidth Generously Provided by pair Networks
Pathologically Eclectic Rubbish Lister
 
PerlMonks  

Re: Burned by precedence rules

by swampyankee (Parson)
on Dec 24, 2008 at 04:26 UTC ( #732408=note: print w/ replies, xml ) Need Help??


in reply to Burned by precedence rules

Like toolic, I work on the principle of "when in doubt, parenthesize." I've also dealt with optimizing compilers that would handle something like

do i = 1, 10 do j = 1, 10 do k = 1, 10 l = i + j + k enddo enddo enddo

differently from

do i = 1, 10 do j = 1, 10 do k = 1, 10 l = (i + j) + k enddo enddo enddo

in that it would not recognize i + j as constant in the innermost loop in the first fragment, but would in the second. There are also cases where I've needed to force a specific order of operations to preclude under or overflow.

I also won't rule out the possibility that, unlike the compiler, I can get confused about logical tests that have multiple and's, or's, and not's; using (perhaps superfluous) parentheses will reduce my confusion.


Information about American English usage here and here. Floating point issues? Please read this before posting. — emc


Comment on Re: Burned by precedence rules
Select or Download Code

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://732408]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others browsing the Monastery: (6)
As of 2014-07-24 03:56 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    My favorite superfluous repetitious redundant duplicative phrase is:









    Results (157 votes), past polls