printf - a flawed but useful function

Many languages have printf statements ... and yet from a computer scientist's viewpoint, printf is a flawed function. In order for code to be clean and re-usable, functions should be designed to perform a single task. Alas, printf performs two tasks - it both formats the information that's entered in to it AND it then sends that information to an output stream.

What's the better alternative? Where you have printf, you probably have sprintf as well and that's a much better function - it just returns you the formatted string. So I'm advocating that, in Perl for example, you should write:

$tstring = sprintf("%02d:%02d",$hour,$min);
print ("Ths time of this record was $tstring\n");
(written 2006-02-22, updated 2006-06-05)

Associated topics are indexed under

H109 - PHP - Input / Output
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  [2964] An introduction to file handling in programs - buffering, standard in and out, and file handles - (2010-09-21)
  [1780] Server overloading - turns out to be feof in PHP - (2008-09-01)
  [1442] Reading a file multiple times - file pointers - (2007-11-23)
  [1113] File and URL reading in PHP - (2007-03-20)
  [1096] Sample script - FTP to get a file from within PHP - (2007-03-01)
  [1094] PHP fread - truncated data - (2007-02-27)
  [997] Most recent file in a directory - PHP - (2006-12-18)
  [709] Handling huge data files in PHP - (2006-05-04)
  [653] Easy feed! - (2006-03-21)
  [114] Relative or absolute milkman - (2004-11-10)

P207 - Perl - File Handling
  [3839] Spraying data from one incoming to series of outgoing files in Perl - (2012-08-15)
  [3830] Traversing a directory in Perl - (2012-08-08)
  [3548] Dark mornings, dog update, and Python and Lua courses before Christmas - (2011-12-10)
  [3326] Finding your big files in Perl - design considerations beyond the course environment - (2011-06-14)
  [2833] Fresh Perl Teaching Examples - part 2 of 3 - (2010-06-27)
  [2821] Chancellor George Osborne inspires Perl Program - (2010-06-22)
  [2818] File open and read in Perl - modernisation - (2010-06-19)
  [2405] But I am reading from a file - no need to prompt (Perl) - (2009-09-14)
  [2233] Transforming data in Perl using lists of lists and hashes of hashes - (2009-06-12)
  [1861] Reactive (dynamic) formatting in Perl - (2008-10-31)
  [1860] Seven new intermediate Perl examples - (2008-10-30)
  [1841] Formatting with a leading + / Lua and Perl - (2008-10-15)
  [1709] There is more that one way - Perl - (2008-07-14)
  [1467] stdout v stderr (Tcl, Perl, Shell) - (2007-12-10)
  [1416] Good, steady, simple example - Perl file handling - (2007-10-30)
  [1312] Some one line Perl tips and techniques - (2007-08-21)
  [867] Being sure to be positive in Perl - (2006-09-15)
  [702] Iterators - expressions tha change each time you call them - (2006-04-27)
  [618] Perl - its up to YOU to check your file opened - (2006-02-23)
  [255] STDIN, STDOUT, STDERR and DATA - Perl file handles - (2005-03-23)
  [12] How many people in a room? - (2004-08-12)

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