1lassign(n)                   Tcl Built-In Commands                  lassign(n)
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NAME

8       lassign - Assign list elements to variables
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SYNOPSIS

11       lassign list ?varName ...?
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DESCRIPTION

15       This command treats the value list as a list and assigns successive el‐
16       ements from that list to the variables given by the  varName  arguments
17       in order.  If there are more variable names than list elements, the re‐
18       maining variables are set to the empty string.  If there are more  list
19       elements than variables, a list of unassigned elements is returned.
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EXAMPLES

22       An illustration of how multiple assignment works, and what happens when
23       there are either too few or too many elements.
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25              lassign {a b c} x y z       ;# Empty return
26              puts $x                     ;# Prints "a"
27              puts $y                     ;# Prints "b"
28              puts $z                     ;# Prints "c"
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30              lassign {d e} x y z         ;# Empty return
31              puts $x                     ;# Prints "d"
32              puts $y                     ;# Prints "e"
33              puts $z                     ;# Prints ""
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35              lassign {f g h i} x y       ;# Returns "h i"
36              puts $x                     ;# Prints "f"
37              puts $y                     ;# Prints "g"
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39       The lassign command has other uses.  It can be used to create the  ana‐
40       logue of the “shift” command in many shell languages like this:
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42              set ::argv [lassign $::argv argumentToReadOff]
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SEE ALSO

45       lindex(n), list(n), lrange(n), lset(n), set(n)
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KEYWORDS

48       assign, element, list, multiple, set, variable
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52Tcl                                   8.5                           lassign(n)
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