string
Manipulate strings
Syntax
string option arg [ arg ... ]
Description
Performs one of several string operations, depending on
option. The legal options (which may be
abbreviated) are:
- string compare string1 string2
- Perform a character-by-character comparison of strings
string1 and string2 in the same way as the C
strcmp procedure. It returns -1, 0, or 1, depending
on whether string1 is lexicographically less than, equal
to, or greater than string2.
- string first string1 string2
- 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.
- 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. If charIndex is less
than 0 or greater than or equal to the length of the string then an
empty string is returned.
- string last string1 string2
- 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.
- string length string
- Returns a decimal string giving the number of characters in
string.
- string match pattern string
- See if pattern matches string; return 1
if it does, 0 if it doesn't. Matching is done in a fashion similar to
that used by the C-shell. 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.
- \x
- Matches the single character x. This
provides a way of avoiding the special interpretation of the
characters *?[]\e 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. Last may be end (or any
abbreviation of it) to refer to the last character of the string. 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 tolower string
- Returns a value equal to string except that all upper
case letters have been converted to lower case.
- string toupper string
- Returns a value equal to string except that all lower
case letters have been converted to upper case.
- 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).