Matching, wildcards and ranges
In a list-lookup, we will test if there exist any records in the list where incoming Key (e.g. caller's phone number, entered DTMF or Subject in an email) matches the Key in a row in the list. If a match is found, the (first) matching record's value is returned.
Please do not use these special characters in the key field since they will not return a match even if there is a match: ú, û, ü, ÷, õ, ý, ù
The incoming Key can only be a single (constant) element. Wildcards or ranges are not allowed here.
The Key field of a record in a list may be a single element (constant), a range, or a single element containing one or more wildcards Combinations of range and wildcard(s) within a list row's Key is not allowed.
Ranges in the list's Key field
- The from-value and the to-value is separated by : (colon)
- The to-value is included in the range. Example Key range: 21000000 : 21999999
Wildcards in the Key field
The wildcard matching, as well as the substitution (next chapter), is based on syntax known from Perl-based regular expressions. Though, there exists a set of restrictions compared to the full Perl syntax. This is what's supported as part of a Key:
- Represent any number of characters: .* (i.e. a single dot followed by an asterisk)
- Represent any single character: . (i.e. a single dot)
Examples:
| Description | Key |
|---|---|
| Match for any number starting with 47 | 47.* |
| Match for numbers starting with 47, and which are 10 digits in total length (i.e. eight digits after 47) | 47........ |
| Match any number starting with 47 and ending with 99. Between the starting 47 and the ending 99, there should be at least two characters. | 47...*99 |
| Match for text ending with abc | .*abc |
| Match for text beginning with abc | abc.* |
| Match for text containing abc | .*abc.* |
Advanced:
Quoting needed for the wildcard characters
If a single dot is going to be part of the key, and not treated as a wildcard, you need to prefix (escape) the dot with a backslash. The same is true for an asterisk if the asterisk follows a single dot. Though, asterisk alone (i.e. not right after a dot) is understood to be part of the key without the backslash. Examples, quoting:
| Description | Key |
|---|---|
| Make a Key that should match an incoming Key with the fixed value 47*1 | 47*1 |
| Make a Key that should match an incoming Key starting with 47, then it should have one character of any kind, immediately followed by *9 (sample of such an incoming Key is 473*9) | 47.\*9 |
| Make a Key that should match an incoming Key with the fixed value 47.1. | 47\.1 |
Substitution:
A return value (from the match in the look-up) can be manipulated so it contains parts of (or the whole) incoming Key. This is how:
- A wildcard expression might be surrounded by parentheses, thereby making a wildcard group
- There might be more than one wildcard group within the same Key. The characters in an incoming Key that matches a particular wilcard group could be part of the returned value.
- Placeholders (in the specified return Value) for these wildcard groups are $1 for the first group, $2 for the second, $3 for the third, and so on.
Examples:
| Description | Set Key to | Set Value to |
|---|---|---|
| Any incoming Key starting with 22, and which are exactly 8 digits, should be prefixed with the value 0047 | 22(......) | 004722$1 |
| Incoming Key starting with 0047, and containing an unknown number of characters thereafter, should have 0047 stripped off. | 0047(.*) | $1 |