[Richard Suchenwirth] 2002-12-06 - Tables are understood here as rectangular (matrix) arrangements of data in rows (one row per "item"/"record") and columns (one column per "field"/"element"). In Tcl, a sensible implementation would be as a list of lists.

A nice table also has a header line, that specifies the field name. So to create such a table with a defined field structure, but no contents yet, one just assigns the header list:
 set tbl {{firstname lastname phone}}
Note the double bracing, which makes sure ''tbl'' is a 1-element list. Adding "records" to the table is as easy as
 lappend tbl {John Smith (123)456-7890}
Here single bracing is correct. If a field content contains spaces, it must be quoted or braced too:
 lappend tbl {{George W} Bush 234-5678}
Sorting a table can be done with lsort -index, taking care that the header line stays on top:
 proc tsort args {
    set table [lindex $args end]
    set header [lindex $table 0]
    set res [eval lsort [lrange $args 0 end-1] [list [lrange $table 1 end]]]
    linsert $res 0 $header
 }
Removing a row (or contiguous sequence of rows) by numeric index is a job for [lreplace]:
 set tbl [lreplace $tbl $from $to]

Simple printing of such a table, a row per line, is easy with
 puts [join $tbl \n]
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See also [matrix].
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[Category Concept] | [Arts and crafts of Tcl-Tk programming]