Regular Expressions

Reference guide for the regular expression syntax supported in string conditions for validation, delivery customization, and payment customization functions.

Regular expressions (regexp) provide pattern matching for string conditions. Two operators are available in the condition builder:

case-sensitive matching
case-insensitive matching

Patterns are unanchored — they match if the pattern is found anywhere in the input string. You don’t need to wrap your pattern in .* to match a substring.

Availability

Regular expressions are available for string conditions in:

Validation functions
Delivery Customization functions
Payment Customization functions

They are not available in Discount or Cart Transform functions.

Supported Syntax

Syntax	Name	Description	Example
`.`	Dot	Matches any single character	`h.llo` matches “hello”, “hallo”
`*`	Star	Zero or more of the previous element	`ab*c` matches “ac”, “abc”, “abbc”
`+`	Plus	One or more of the previous element	`ab+c` matches “abc”, “abbc” but not “ac”
`\|`	Alternation	Matches either side	`cat\|dog` matches “cat” or “dog”
`()`	Grouping	Groups elements together	`(ab)+` matches “ab”, “abab”
`\`	Escape	Treats next character as literal	`a\.b` matches “a.b” but not “axb”

Combining Operators

Operators can be combined to build more complex patterns:

.* — matches any sequence of characters (zero or more)
.+ — matches any sequence of characters (one or more)
(cat|dog)+ — matches one or more occurrences of “cat” or “dog”
(a|b)*c — matches “c”, “ac”, “bc”, “aac”, “abc”, etc.

Examples

Address Matching

Detect P.O. Box addresses:

Pattern: p.*o.*(box)*
Operator: RegExp*

Matches: "PO Box 123", "P.O. Box 456", "Post Office Box 789"

SKU Patterns

Match a SKU format like “ABC-123”:

Pattern: ...-...
Operator: RegExp

Matches: "ABC-123", "XYZ-999"

Email Validation

Check if a value looks like an email:

Pattern: .+@.+
Operator: RegExp

Matches: "user@example.com"
Does not match: "no-at-sign"

Product Tags

Match products with specific tag patterns:

Pattern: premium|vip|exclusive
Operator: RegExp*

Matches: "Premium", "VIP", "exclusive", "PREMIUM-MEMBER"

Country Code Prefixes

Match phone numbers starting with specific country codes:

Pattern: \+1|011
Operator: RegExp

Matches: "+1-555-0100", "011-44-20"

Escaping Special Characters

If you need to match a character that has special meaning (. * + | ( ) \), prefix it with a backslash:

To match	Use
Literal `.`	`\.`
Literal `*`	`\*`
Literal `+`	`\+`
Literal `\|`	`\|`
Literal `(`	`\(`
Literal `)`	`\)`
Literal `\`	`\\`

What’s Not Supported

The regexp engine uses a minimal syntax optimized for performance. The following features are not available:

Character classes: [a-z], [^abc], [0-9]
Anchors: ^ (start), $ (end)
Optional quantifier: ?
Repetition counts: {n}, {n,m}
Shorthand classes: \d, \w, \s
Backreferences
Lookahead / lookbehind
Named or capturing groups

Tips

Patterns are unanchored — hello matches “say hello world”. You don’t need .*hello.*.
Use alternation for multiple keywords — error|warning|critical matches any of the three words.
Keep patterns simple — the supported syntax covers most common matching needs without the complexity of full regular expressions.