- string bytelength string
- Returns a decimal string giving the number of bytes used to
represent string in memory. Because UTF-8 uses one to three
bytes to represent Unicode characters, the byte length will not be
the same as the character length in general. The cases where a
script cares about the byte length are rare. In almost all cases,
you should use the string length operation (including
determining the length of a Tcl ByteArray object). Refer to the
Tcl_NumUtfChars manual entry
for more details on the UTF-8 representation.
- string compare ?-nocase? ?-length
int? string1 string2
- Perform a character-by-character comparison of strings
string1 and string2. Returns -1, 0, or 1, depending
on whether string1 is lexicographically less than, equal to,
or greater than string2. If -length is specified,
then only the first length characters are used in the
comparison. If -length is negative, it is ignored. If
-nocase is specified, then the strings are compared in a
case-insensitive manner.
- string equal ?-nocase? ?-length
int? string1 string2
- Perform a character-by-character comparison of strings
string1 and string2. Returns 1 if string1 and
string2 are identical, or 0 when not. If -length is
specified, then only the first length characters are used in
the comparison. If -length is negative, it is ignored. If
-nocase is specified, then the strings are compared in a
case-insensitive manner.
- string first string1 string2
?startIndex?
- Search string2 for a sequence of characters that exactly
match the characters in string1. If found, return the index
of the first character in the first such match within
string2. If not found, return -1. If startIndex is
specified (in any of the forms accepted by the index
method), then the search is constrained to start with the character
in string2 specified by the index. For example,
string first a 0a23456789abcdef 5
will return 10, but
string first a 0123456789abcdef 11
will return -1.
- string index string
charIndex
- Returns the charIndex'th character of the string
argument. A charIndex of 0 corresponds to the first
character of the string. charIndex may be specified as
follows:
- integer
- The char specified at this integral index.
- end
- The last char of the string.
- end-integer
- The last char of the string minus the specified integer offset
(e.g. end-1 would refer to the "c" in "abcd").
If charIndex is less than 0 or greater than or equal to
the length of the string then an empty string is returned.
- string is class ?-strict?
?-failindex varname? string
- Returns 1 if string is a valid member of the specified
character class, otherwise returns 0. If -strict is
specified, then an empty string returns 0, otherwise and empty
string will return 1 on any class. If -failindex is
specified, then if the function returns 0, the index in the string
where the class was no longer valid will be stored in the variable
named varname. The varname will not be set if the
function returns 1. The following character classes are recognized
(the class name can be abbreviated):
- alnum
- Any Unicode alphabet or digit character.
- alpha
- Any Unicode alphabet character.
- ascii
- Any character with a value less than \u0080 (those that are in
the 7-bit ascii range).
- boolean
- Any of the forms allowed to Tcl_GetBoolean.
- control
- Any Unicode control character.
- digit
- Any Unicode digit character. Note that this includes characters
outside of the [0-9] range.
- double
- Any of the valid forms for a double in Tcl, with optional
surrounding whitespace. In case of under/overflow in the value, 0
is returned and the varname will contain -1.
- false
- Any of the forms allowed to Tcl_GetBoolean where the value is
false.
- graph
- Any Unicode printing character, except space.
- integer
- Any of the valid forms for an ordinary integer in Tcl, with
optional surrounding whitespace. In case of under/overflow in the
value, 0 is returned and the varname will contain -1.
- lower
- Any Unicode lower case alphabet character.
- print
- Any Unicode printing character, including space.
- punct
- Any Unicode punctuation character.
- space
- Any Unicode space character.
- true
- Any of the forms allowed to Tcl_GetBoolean where the value is
true.
- upper
- Any upper case alphabet character in the Unicode character
set.
- wordchar
- Any Unicode word character. That is any alphanumeric character,
and any Unicode connector punctuation characters (e.g.
underscore).
- xdigit
- Any hexadecimal digit character ([0-9A-Fa-f]).
In the case of boolean, true and false, if
the function will return 0, then the varname will always be
set to 0, due to the varied nature of a valid boolean value.
- string last string1 string2
?lastIndex?
- Search string2 for a sequence of characters that exactly
match the characters in string1. If found, return the index
of the first character in the last such match within
string2. If there is no match, then return -1. If
lastIndex is specified (in any of the forms accepted by the
index method), then only the characters in string2 at
or before the specified lastIndex will be considered by the
search. For example,
string last a 0a23456789abcdef 15
will return 10, but
string last a 0a23456789abcdef 9
will return 1.
- string length string
- Returns a decimal string giving the number of characters in
string. Note that this is not necessarily the same as the
number of bytes used to store the string. If the object is a
ByteArray object (such as those returned from reading a binary
encoded channel), then this will return the actual byte length of
the object.
- string map ?-nocase? mapping
string
- Replaces substrings in string based on the key-value
pairs in mapping. mapping is a list of key value
key value ... as in the form returned by array get. Each instance of a key in
the string will be replaced with its corresponding value. If
-nocase is specified, then matching is done without regard
to case differences. Both key and value may be
multiple characters. Replacement is done in an ordered manner, so
the key appearing first in the list will be checked first, and so
on. string is only iterated over once, so earlier key
replacements will have no affect for later key matches. For
example,
string map {abc 1 ab 2 a 3 1 0} 1abcaababcabababc
will return the string 01321221.
Note that if an earlier key is a prefix of a later one,
it will completely mask the later one. So if the previous example
is reordered like this,
string map {1 0 ab 2 a 3 abc 1} 1abcaababcabababc
it will return the string 02c322c222c.
- string match ?-nocase?
pattern string
- See if pattern matches string; return 1 if it
does, 0 if it doesn't. If -nocase is specified, then the
pattern attempts to match against the string in a case insensitive
manner. For the two strings to match, their contents must be
identical except that the following special sequences may appear in
pattern:
- *
- Matches any sequence of characters in string, including
a null string.
- ?
- Matches any single character in string.
- [chars]
- Matches any character in the set given by chars. If a
sequence of the form x-y appears in
chars, then any character between x and y,
inclusive, will match. When used with -nocase, the end
points of the range are converted to lower case first. Whereas
{[A-z]} matches '_' when matching case-sensitively ('_' falls
between the 'Z' and 'a'), with -nocase this is considered
like {[A-Za-z]} (and probably what was meant in the first
place).
- \x
- Matches the single character x. This provides a way of
avoiding the special interpretation of the characters *?[]\
in pattern.
- string range string first
last
- Returns a range of consecutive characters from string,
starting with the character whose index is first and ending
with the character whose index is last. An index of 0 refers
to the first character of the string. first and last
may be specified as for the index method. If first is
less than zero then it is treated as if it were zero, and if
last is greater than or equal to the length of the string
then it is treated as if it were end. If first is
greater than last then an empty string is returned.
- string repeat string count
- Returns string repeated count number of
times.
- string replace string first last
?newstring?
- Removes a range of consecutive characters from string,
starting with the character whose index is first and ending
with the character whose index is last. An index of 0 refers
to the first character of the string. First and last
may be specified as for the index method. If
newstring is specified, then it is placed in the removed
character range. If first is less than zero then it is
treated as if it were zero, and if last is greater than or
equal to the length of the string then it is treated as if it were
end. If first is greater than last or the
length of the initial string, or last is less than 0, then
the initial string is returned untouched.
- string tolower string
?first? ?last?
- Returns a value equal to string except that all upper
(or title) case letters have been converted to lower case. If
first is specified, it refers to the first char index in the
string to start modifying. If last is specified, it refers
to the char index in the string to stop at (inclusive).
first and last may be specified as for the
index method.
- string totitle string
?first? ?last?
- Returns a value equal to string except that the first
character in string is converted to its Unicode title case
variant (or upper case if there is no title case variant) and the
rest of the string is converted to lower case. If first is
specified, it refers to the first char index in the string to start
modifying. If last is specified, it refers to the char index
in the string to stop at (inclusive). first and last
may be specified as for the index method.
- string toupper string
?first? ?last?
- Returns a value equal to string except that all lower
(or title) case letters have been converted to upper case. If
first is specified, it refers to the first char index in the
string to start modifying. If last is specified, it refers
to the char index in the string to stop at (inclusive).
first and last may be specified as for the
index method.
- string trim string
?chars?
- Returns a value equal to string except that any leading
or trailing characters from the set given by chars are
removed. If chars is not specified then white space is
removed (spaces, tabs, newlines, and carriage returns).
- string trimleft string
?chars?
- Returns a value equal to string except that any leading
characters from the set given by chars are removed. If
chars is not specified then white space is removed (spaces,
tabs, newlines, and carriage returns).
- string trimright string
?chars?
- Returns a value equal to string except that any trailing
characters from the set given by chars are removed. If
chars is not specified then white space is removed (spaces,
tabs, newlines, and carriage returns).
- string wordend string
charIndex
- Returns the index of the character just after the last one in
the word containing character charIndex of string.
charIndex may be specified as for the index method. A
word is considered to be any contiguous range of alphanumeric
(Unicode letters or decimal digits) or underscore (Unicode
connector punctuation) characters, or any single character other
than these.
- string wordstart string
charIndex
- Returns the index of the first character in the word containing
character charIndex of string. charIndex may
be specified as for the index method. A word is considered
to be any contiguous range of alphanumeric (Unicode letters or
decimal digits) or underscore (Unicode connector punctuation)
characters, or any single character other than these.
