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unset(n) [osx man page]

unset(n)						       Tcl Built-In Commands							  unset(n)


unset - Delete variables SYNOPSIS
unset ?-nocomplain? ?--? ?name name name ...? _________________________________________________________________ DESCRIPTION
This command removes one or more variables. Each name is a variable name, specified in any of the ways acceptable to the set command. If a name refers to an element of an array then that element is removed without affecting the rest of the array. If a name consists of an array name with no parenthesized index, then the entire array is deleted. The unset command returns an empty string as result. If -nocom- plain is specified as the first argument, any possible errors are suppressed. The option may not be abbreviated, in order to disambiguate it from possible variable names. The option -- indicates the end of the options, and should be used if you wish to remove a variable with the same name as any of the options. If an error occurs, any variables after the named one causing the error are not deleted. An error can occur when the named variable does not exist, or the name refers to an array element but the variable is a scalar, or the name refers to a variable in a non-existent namespace. EXAMPLE
Create an array containing a mapping from some numbers to their squares and remove the array elements for non-prime numbers: array set squares { 1 1 6 36 2 4 7 49 3 9 8 64 4 16 9 81 5 25 10 100 } puts "The squares are:" parray squares unset squares(1) squares(4) squares(6) unset squares(8) squares(9) squares(10) puts "The prime squares are:" parray squares SEE ALSO
set(n), trace(n), upvar(n) KEYWORDS
remove, variable Tcl 8.4 unset(n)

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set(n)							       Tcl Built-In Commands							    set(n)


set - Read and write variables SYNOPSIS
set varName ?value? _________________________________________________________________ DESCRIPTION
Returns the value of variable varName. If value is specified, then set the value of varName to value, creating a new variable if one doesn't already exist, and return its value. If varName contains an open parenthesis and ends with a close parenthesis, then it refers to an array element: the characters before the first open parenthesis are the name of the array, and the characters between the parentheses are the index within the array. Otherwise varName refers to a scalar variable. Normally, varName is unqualified (does not include the names of any containing namespaces), and the variable of that name in the current namespace is read or written. If varName includes names- pace qualifiers (in the array name if it refers to an array element), the variable in the specified namespace is read or written. If no procedure is active, then varName refers to a namespace variable (global variable if the current namespace is the global namespace). If a procedure is active, then varName refers to a parameter or local variable of the procedure unless the global command was invoked to declare varName to be global, or unless a variable command was invoked to declare varName to be a namespace variable. SEE ALSO
expr(n), proc(n), trace(n), unset(n) KEYWORDS
read, write, variable Tcl set(n)
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