Writing Code For Others

http://www.codinghorror.com/blog/

amol.pujari@gslab.com

Why

http://www.makinggoodsoftware.com/

Writing Code For Others

why do we write code?

• to get it executed by a machine• the machine understands 0s and 1s only• then why do we use high level languages like c,

java, or ruby• did the machine request us to use c or ruby?

http://sourcemaking.com/

we use high level languages so humans can understand code by

reading it

http://www.makinggoodsoftware.com/2009/07/07/5-top-non-technical-mistakes-made-by-programmers/

how do others find reading your code?

• do they find it helpful in understanding your program–the optimizations you’ve done–your naming conventions, your coding style–how long they should take to do it–more importantly, would they like looking at your

code–would they love the way you code• or do they simply find it quite boring

http://stackoverflow.com/questions/1711/what-is-the-single-most-influential-book-every-programmer-should-read

you can help others to quickly read your code and understand it

http://www.joelonsoftware.com/articles/Wrong.html

characteristics of good code

• easy to read• easy to use• clean, simple, straight forward• easy to make any changes• self explanatory• short methods, clear names• consistent coding standards

http://www.thoughtclusters.com/2010/09/characteristics-of-great-programmers/

writing necessary comments

http://www.makinggoodsoftware.com/2009/09/01/programmers-top-10-sentences/

writing necessary comments

• let’s define “necessary” comments

http://en.wikipedia.org/wiki/Code_smell

writing necessary comments

• should not tell us how code works• but why code works• convert your comments into variable names or

function names, constants

http://en.wikipedia.org/wiki/Anti-pattern#Programming_anti-patterns

follow same indentations

• different people love different editors• tab is treated differently by different editors• define tab = 2 or 4 spaces• good if entire team follows same definition of

tab

http://www.makinggoodsoftware.com/2011/05/23/top-7-programmers-bad-habits/

more than indentations

http://www.makinggoodsoftware.com/2010/05/27/10-things-they-never-teach-in-college-about-programming/

more than indentations

http://www.makinggoodsoftware.com/2010/03/13/my-ten-development-principles/

write working pseudo code

•write a program• given a number• print “divisible by 3” if it is divisible by 3• print “divisible by 5 if it is divisible by 5• print “divisible by 15” if it is divisible by 15

http://www.codinghorror.com/blog/2009/05/pseudocode-or-code.html

write working pseudo code

•write a program• given a number• print “divisible by 3” if it is divisible by 3• print “divisible by 5 if it is divisible by 5• print “divisible by 15” if it is divisible by 15

http://www.codinghorror.com/blog/2009/05/pseudocode-or-code.html

write working pseudo code

• you might have simply optimized• reducing one divide operation

write working pseudo code

•write a program• given a number• print “divisible by 3” if it is divisible by 3• print “divisible by 5 if it is divisible by 5- a change requestprint “divisible by 15” if it is divisible by 15print “divisible by 17” if it is divisible by 17

http://stackoverflow.com/questions/84556/whats-your-favorite-programmer-cartoon

write working pseudo code

• If pseudo code would have been followed•without optimizations

nested if-else

http://tinyletter.com/codereading

nested if-else

• avoid nested if-else chain• use switch or multiple returns• same follows for iterators while, for

http://inter-sections.net/2007/11/13/how-to-recognise-a-good-programmer

god class

• a file or class or a module• knows too much or does too much• contains more than 1000 or 5000 loc• class with a large number of attributes,

operations, or both• uses heavy encapsulation

http://www.dehora.net/journal/2005/06/writing_code_for_others_that_use_it.html

long methods

•would you like to read and understand a function which is of 300 lines or say 1000 lines

• or would you like to understand functions with 10 lines, 20, say 30 lines at the most

http://www.dmst.aueb.gr/dds/pubs/jrnl/2003-ACMQ-CR/html/article.html

one function one responsibility

http://www.skorks.com/2010/05/why-i-love-reading-other-peoples-code-and-you-should-too/

one function one responsibility

http://rubylearning.com/blog/2010/11/08/how-does-your-code-smell/

long parameters list

http://www.codinghorror.com/blog/2006/05/code-smells.html

more coding horrors

• uncommunicative name - naming functions and variables•magic numbers, hardcoded values• data clumps• feature Envy•middle man …and more

http://www.codinghorror.com/blog/2006/05/code-smells.html

characteristics of a good code

• easy to read• easy to understand• easy to make any changes• clean, simple• looks straight forward• self explanatory• short methods, clear names

http://www.perlmonks.org/?node_id=592616

characteristics of good code

• easy to read• easy to use• clean, simple, straight forward• easy to make any changes• self explanatory• short methods, clear names• consistent coding standards

http://www.thoughtclusters.com/2010/09/characteristics-of-great-programmers/

characteristics of a good coder

• likes to read code written by well known programmers• likes to do code review of junior or senior

colleagues• participates in pair programming• learns new things weekly w.r.t. coding• does not make unnecessary complex

optimizations• does not refractor working code again and

again

and what else would you like to suggest?

http://sourcemaking.com/refactoring

enjoy coding

http://www.artima.com/intv/ruby.html