'''`[array] set`''' sets values in an array.


** Synopsis **

'''`[array] set`''' ''`arrayName list`''



** Description **

Sets the values of one or more elements in ''`arrayName`''. ''`list`'' must have a form like that returned by '''`[array get]`''', consisting of an even number of elements.  Each odd-numbered element in ''`list`'' is treated as an element name within ''`larrayName`'', and the following element in ''`list`'' is used as a new value for that array element. If the variable ''`arrayName`'' does not already exist and ''`list`'' is empty, ''`arrayName`'' is created with an empty array value.

For example,

======none
array set val [list a 1 c 6 d 3]
puts $val(a)
1
puts $val(c)
6
puts $val(d)
3
====== 

Example using lindex:

======
set port {a 1}
array set val [list [lindex $port 0] [lindex $port 1]]
set val([lindex $port 0]) ;# -> 1
======

Note that `array set` does not remove
elements which already exist in the array.
For example,

====== 
array set spam {} ;# This does not work
====== 

...will not clear out the array ''spam''.
To clear an array, can use [array unset]
in version 8.3 and beyond.
For example:

====== 
array unset spam
====== 

...will remove the array ''spam'' if it exists, but will not complain if it does not.

====== 
array unset spam *
====== 

...will clear the contents of the array ''spam'', but the array will continue to exist.

This feature makes it easier to work with array variables,
but it can come as a surprise to those who expected
''array set'' to act like the normal [set] command
(which replaces any existing data in the variable).
It might be useful to think of it as ''array append''.

[RS]:  Sometimes [array set] adds new elements (appending implies some order, which arrays don't so clearly have), sometimes it replaces existing elements. So I still think the name [array set] is clearer...


----

[RFox] 2012-03-14: A better name might have been ''array merge'' as that describes exactly what it does.. it merges the list of index/value into the named array creating it if needed.  The term merge implies the possible replacement of existing indices and creation of new ones.


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