New in Tcl? Coming from another language? Read on.

This could be fun. I learned almost all of my programming with [PHP], and a little bit of [Perl]. This sheet [http://www.cs.tufts.edu/g/20/notes/php_perl.php] helped me an awful lot when I tried to learn [Perl], so a Tcl cheat sheet may be awfully useful to someone else. Feel free to add other languages.

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'''PHP:'''  file.php3

'''PERL:'''  file.cgi

'''TCL:'''  file.tcl
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'''PHP:'''  scripts in <?php..?>

'''PERL:'''  whole file is script

'''TCL:'''  whole file is script
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'''PHP:'''  can include raw HTML

'''PERL:'''  must print all output

'''TCL:'''  must print all output
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'''PHP:'''  no requirements for first line

'''PERL:'''  first line is #!/local/bin/perl  (but is that a requirement?)

'''TCL:'''  first line can be #!/local/bin/tclsh  (but that is no requirement)
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'''protections'''

'''PHP:'''  not executable file

'''PERL:'''  executable file

'''TCL:'''  What the heck? You can make almost any file executable in nix platforms!
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'''PHP:'''  chmod 644 file.php3

'''PERL:'''  chmod 755 file.cgi

'''TCL:'''  er... I don't know
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'''printing'''

'''PHP:'''  echo "stuff\n";

'''PERL:'''  print "stuff\n";

'''TCL:'''  puts stuff  '''OR'''  puts "some stuff"  '''OR''' puts {some stuff}
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'''variables'''

'''PHP:'''  All variables $var

'''PERL:'''  $var is a scalar variable.

'''TCL:'''  '''var''' or '''$var''' - more detailed explanation needed here. See [set]
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'''PHP:'''  $var always means one thing

'''PERL:'''  $var, @var, %var, var are different things!

'''TCL:'''  $var and var always means one thing (???)
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'''arrays'''

'''PHP:'''  $var = array(1,2,3);

'''PERL:'''  @var = (1,2,3);

'''TCL:'''  well, there are lists...

 set var "1 2 3"  '''OR'''  set var [[ list 1 2 3 ]]

and arrays...

 array set var "key1 value1 key2 value2 key3 value3"

'''PHP:'''  "numeric" arrays and "associative" arrays

'''PERL:'''  "arrays" and "hashes"

'''TCL:'''  "lists" and "arrays"


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'''PHP:'''  $var[[1]] is second element of $var

'''PERL:'''  $var[[1]] is second element of @var

'''TCL:'''  [[ lindex $var 1 ]] is second element of $var
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'''PHP:'''  count($var) is length

'''PERL:'''  scalar(@var) is length

'''TCL:'''  [[ llength $var ]] is length
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'''PHP:'''  for ($i=0; $i<count($var); $i++) echo $var[[$i]];

'''PERL:'''  foreach $thing (@var) { print $thing; }

'''TCL:'''  for { set i 0 }  {$i < [[ llength $var ]] }  { incr i }  { puts [[ lindex $var $i ]] }
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'''PHP:'''  join(":",array(1,2,3))

'''PERL:'''  join(":",(1,2,3))

'''TCL:'''  join [[ list 1 2 3 ]] :   (yeah, yeah, you can wrap the colon in quotes if you're queasy)
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'''objects'''

'''PHP:'''  associative arrays are arrays

'''PERL:'''  associative arrays are their own type

'''TCL:'''  Er... what is a "type"?  ;-)
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'''PHP:'''  $var = array(1=>"ho","hi"=>4);

'''PERL:'''  %var = (1=>"ho","hi"=>4);

'''TCL:'''  array set var "1 ho hi 4"
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'''PHP:'''  $var[['ho']] is element indexed by 'ho'

'''PERL:'''  $var{'ho'} is element of %var

'''TCL:'''  $var[['ho']] is element indexed by 'ho'  '''confusing???'''
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'''PHP:'''  while (list($k,$v) = each $var)) {...}

'''PERL:'''  while (($k,$v) = each %var) {...}

'''TCL:'''  er...  foreach { key value } [[ array get var ]]  {...}
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'''to be continued...'''

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[Category ???]