gives a list of the substrings in "string" that match the string expression patt.


gives a list of the values of rhs corresponding to the substrings that match the string expression lhs.


includes only the first n substrings that match.


gives substrings that match any of the pi.


gives the list of results for each of the si.


represents an operator form of StringCases that can be applied to an expression.

Details and Options

Background & Context


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Basic Examples  (3)

Find the substrings matching a pattern:

Return only the named wild-card character in each substring:

Use the operator form of StringCases:

Scope  (8)

Use string patterns:

Use a regular expression:

Use pattern matching for dates:

Mixed regular expressions and string patterns:

Rules to extract values corresponding to matching substrings:

Include only the two first strings that match:

Occurrences in either substring:

StringCases automatically threads over lists of strings:

Options  (2)

IgnoreCase  (1)

Find all substrings "cat", including use of uppercase letters:

Overlaps  (1)

Find all runs of two or more letters starting with the letter "a":

Allow overlaps between the substrings:

Allow multiple substrings to start at the same character as well:

Applications  (3)

Extract phone numbers from a text:

Find the sequence of section numbers in the US Constitution:

Find the numbers of amendments to the Constitution:

Primes whose digits are all consecutive:

Properties & Relations  (2)

StringCount gives the number of matching substrings:

The length of matching substrings:

Use StringPosition to get the position of matching substrings:


Possible Issues  (1)

Use :> rather than -> if the right-hand side of a rule contains string operations:

Using -> in such cases leads to immediate evaluation and possible error messages:

Neat Examples  (1)

Find the sequence of words in the US Constitution:

Total number of words:

Number of distinct words:

Logarithmic frequency distribution of words:

Ten most common words:

Introduced in 2004
Updated in 2015