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- String Aggregation Operators
String Aggregation Operators¶
String expressions, with the exception of
$concat, only have a well-defined behavior for strings of ASCII characters.
$concat behavior is well-defined regardless of the
characters used.
Note
For details on specific operator, including syntax and examples, click on the specific operator to go to its reference page.
| Name | Description |
|---|---|
$concat |
Concatenates any number of strings. |
$indexOfBytes |
Searches a string for an occurence of a substring and returns the
UTF-8 byte index of the first occurence. If the substring is not
found, returns -1. |
$indexOfCP |
Searches a string for an occurence of a substring and returns the
UTF-8 code point index of the first occurence. If the
substring is not found, returns -1. |
$split |
Splits a string into substrings based on a delimiter. Returns an array of substrings. If the delimiter is not found within the string, returns an array containing the original string. |
$strLenBytes |
Returns the number of UTF-8 encoded bytes in a string. |
$strLenCP |
Returns the number of UTF-8 code points in a string. |
$strcasecmp |
Performs case-insensitive string comparison and returns: 0 if two
strings are equivalent, 1 if the first string is greater than the
second, and -1 if the first string is less than the second. |
$substr |
Deprecated. Use $substrBytes or $substrCP. |
$substrBytes |
Returns the substring of a string. Starts with the character at the specified UTF-8 byte index (zero-based) in the string and continues for the specified number of bytes. |
$substrCP |
Returns the substring of a string. Starts with the character at the specified UTF-8 code point (CP) index (zero-based) in the string and continues for the number of code points specified. |
$toLower |
Converts a string to lowercase. Accepts a single argument expression. |
$toUpper |
Converts a string to uppercase. Accepts a single argument expression. |