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NAME
split - Split a string into a proper Tcl list
SYNOPSIS
split string ?splitChars? ______________________________________________________________________________
DESCRIPTION
Returns a list created by splitting string at each character that is in the splitChars argument. Each element of the result list will consist of the characters from string that lie between instances of the characters in splitChars. Empty list elements will be generated if string contains adjacent characters in splitChars, or if the first or last character of string is in splitChars. If splitChars is an empty string then each character of string becomes a separate element of the result list. SplitChars defaults to the standard white-space characters.
EXAMPLES
Divide up a USENET group name into its hierarchical components:
split
"comp.lang.tcl" .
→ comp lang tcl
See how the split command splits on every character in splitChars, which can result in information loss if you are not careful:
split
"alpha beta gamma" "temp"
→ al {ha b} {} {a ga} {} a
Extract the list words from a string that is not a well-formed list:
split
"Example with {unbalanced brace character"
→ Example with \{unbalanced brace character
Split a string into its constituent characters
split
"Hello world" {}
→ H e l l o { } w o r l d
PARSING
RECORD-ORIENTED FILES
Parse a Unix /etc/passwd file, which consists of one entry
per line, with each line consisting of a colon-separated
list of fields:
## Read the
file
set fid [open /etc/passwd]
set content [read $fid]
close $fid
## Split into
records on newlines
set records [split $content "\n"]
## Iterate over
the records
foreach rec $records {
## Split into
fields on colons
set fields [split $rec ":"]
## Assign
fields to variables and print some out...
lassign $fields \
userName password uid grp longName homeDir shell
puts "$longName uses [file tail $shell] for a login
shell"
}
SEE ALSO
join(3tcl), list(3tcl), string(3tcl)
KEYWORDS
list, split, string