{"id":103,"date":"2008-04-24T22:44:29","date_gmt":"2008-04-24T17:14:29","guid":{"rendered":"http:\/\/www.bin-co.com\/blog\/?p=103"},"modified":"2008-04-24T22:44:29","modified_gmt":"2008-04-24T17:14:29","slug":"hello-script-for-tcl","status":"publish","type":"post","link":"https:\/\/www.bin-co.com\/blog\/2008\/04\/hello-script-for-tcl\/","title":{"rendered":"Hello Script for Tcl"},"content":{"rendered":"

Tcl Logo<\/p>\n

Tcl, or Tool Command Language<\/a>, will not be found in the ‘most popular languages’ hall of fame. That is partly because of its ‘wierd’ syntax. But those who know Tcl will tell you that Tcl is a pleasure to work with. I have a special interest in Tcl – its the language that introduced me to GUI programming(Tcl\/Tk<\/a>). Now, when ever I see a GUI toolkit, I compare it to Tcl<\/a>.<\/p>\n

I have a few years experience in Tcl – I have written a very popular Tcl\/Tk Tutorial<\/a> and also a few<\/a> small<\/a> applications<\/a> in Tcl. I am not using it a lot now a days because Tk apps look really bad in Linux. This problem is not present in Windows.<\/p>\n

Hello Code<\/h3>\n
\n#!\/usr\/bin\/tclsh\n\n# Printing(IO)\nputs \"Hello World!\\n\" \n\n# Variables, concatenation\nset name 'Binny' \nset year 2008 \nputs [concat \"Hello, \"  $name  \" - welcome to \"  $year]\n\n#If,else conditions\nif { $year > 2008 } {\n\t puts \"Welcome to the future - yes, we have flying cars!\" \n\n} elseif { $year < 2008 }  {\n\t puts \"The past - please don't change anything. Don't step on any butterflies. And for the sake of all that's good and holy, stay away from your parents!\" \n\n} else {\n\t puts \"Anything wrong with your time machine? You have not gone anywhere, kiddo.\" \n}\n\n# For loop\nfor { set i 0 } { $i<3 } { incr i  }  { \n\t puts \"$i) Hi there!\" \n}\n\n#Numerical Array, foreach\nset rules [list \"Do no harm\" \"Obey\" \"Continue Living\"]\n\nset i 0\nwhile { $i < [llength $rules] } {\n\tputs [concat \"Rule \" [expr $i+1] \" : \"  [lindex $rules $i]]\n\tincr i \n}\n\n# Associated array, while\narray set associated {\n\thello\t\"world\"\n\tfoo\t\t\"bar\"\n\tlorem\t\"ipsum\"\n}\n\nforeach key [array names associated] {\n\t puts [concat $key \" : \" $associated($key)]\n}\n\n# Using Join and Split\nset csv_values [split \"hello,world,how,are,you\\n\" \",\"]\nputs [join $csv_values \":\"]\n\n# Function, argument, return, call\nproc hello { person_name } {\n\treturn [concat \"Hello, \" $person_name]\n}\nputs [hello \"Binny\"]\n\n# File IO\n# File reading, easy method...\nset IN [open \"Hello.tcl\" r]\nset contents [read $IN]\nclose $IN\nputs [concat \"Hello has \" [string length $contents] \" chars\"]\n\n# Writing to a file\nset OUT [open \"\/tmp\/hello.txt\" w]\nputs $OUT \"Hello World\"\nclose $OUT\n\n# Regular Expressions\nset str \"Hello World\" \nif { [regexp {^Hell} $str] } {\n\tputs \"Yup, its evil\"\n}\n\nputs [regsub -all {l([^l])} $str {\\1}]\n\n# Special Tcl Syntax\n# Math ops\nset answer [expr {3 + 2}]\n\n# Comments\nputs $answer ;# Comments in the same line as code must use ;# instead of just #\n\n<\/code><\/pre>\n
Tcl\/Tk Links<\/h3>\n