For 2023 - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.
Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!
I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
Passing arrays to procs in Tcl
If you're writing a Tcl proc, you'll normally pass in parameters by value, specifying a $ in front of the variable whos contents you want to pass in in the calling sequence:
If, however, passin is a Tcl array, tis won't work since $passin cannot be expanded to string. So you'll need to make the call using:
and then use upvar within the proc to access the data.
INDIVIDUAL ELEMENTS of an array CAN be passed in to a Tcl Proc by value as they're simple strings:
or dojob $passin($elname)
References: our Procedures and Variable Scope
and Tcl Array
(written 2004-11-18, updated 2006-06-05)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articlesT208 - Tcl/Tk - Arrays and dicts 
The fragility of pancakes - and better structures - (2006-06-26) 
Stringing together Tcl scripts - (2007-07-29) 
Generating traffic for network testing - (2007-07-29) 
Sorting in Tcl - lists and arrays - (2007-10-24) 
Arrays in Tcl - a demonstration - (2007-11-10) 
When an array is not an array - (2008-04-17) 
Tcl - passing arrays and strings in and back out of procs - (2009-10-22) 
Tcl - Some example of HOW TO in handling data files and formats - (2011-03-04) 
User defined sorting and other uses of callbacks in Tcl and Tk - (2011-09-02) 
Tcl collections - lists, dicts and array - (2012-01-16) 
Tcl - dicts - a tutorial and examples - (2012-02-14) 
Sorting dicts and arrays in Tcl - (2012-03-04)T207 - Tcl/Tk - Procedures and Variable Scope 
Variable Scope - (2004-10-22) 
Call by name v call by value - (2005-05-11) 
Functions and commands with dangerous names - (2005-08-11) 
Do not duplicate your code - (2006-06-23) 
A better alternative to cutting and pasting code - (2007-04-26) 
Tcl - global, upvar and uplevel. - (2007-10-24) 
Calling procs in Tcl and how it compares to Perl - (2008-09-02) 
Tcl - uplevel to run code at calling level - (2009-10-24) 
Global and Enable - two misused words! - (2009-11-30) 
Passing a variable number of parameters in to a function / method - (2010-08-20) 
Passing back multiple results in Tcl - upvar and uplevel - (2011-09-01) 
Sharing lots of values in Tcl without having lots of global declarations - (2012-02-28) 
Accessing variables across subroutine boundaries - Perl, Python, Java and Tcl - (2015-01-18)
Some other Articles
Feedback shows the tip of an icebergStaff theftPHP v JavaShort underground journeys and a PHP bookPassing arrays to procs in TclFair and SimpleGood early morningPHP course. Come by train.History around youA case of case
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