In CMake, the {n} syntax of regex is used to specify the number of times a pattern should be repeated in a regular expression. This syntax allows you to match patterns that occur a specific number of times in a string.
For example, if you have a string "aaaabbbccc" and you want to match the pattern "a" occurring exactly four times, you can use the regex "[a]{4}".
In CMake, you can use the {n} syntax with the MATCHES operator to check if a string matches a specific pattern with a specified repetition. This can be useful when validating input strings or performing pattern matching in CMake scripts.
Overall, the {n} syntax of regex with CMake allows you to specify the number of occurrences of a pattern in a string, making it a powerful tool for pattern matching and validation tasks in CMake scripts.
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How to use {n} syntax of regex with cmake to ignore case sensitivity in matching?
To use the {n} syntax of regex with cmake to ignore case sensitivity in matching, you can use the following syntax:
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if ("${my_string}" MATCHES "[a-zA-Z]{n}") message("String matches regex with n characters in any case") endif() |
In this syntax, [a-zA-Z] matches any alphabetic character in either uppercase or lowercase, and {n} specifies the exact number of characters to match. By including both uppercase and lowercase characters in the character set, the regex pattern will match the specified number of characters regardless of their case.
How to use {n} syntax of regex with cmake to validate input data?
To use the {n} syntax of regex with CMake to validate input data, you can use the string(REGEX MATCH) command in your CMake script. The {n} syntax allows you to specify the exact number of occurrences of a pattern that you want to match in the input data.
Here is an example of how you can use the {n} syntax in CMake to validate input data:
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# Define the input data set(input_data "12345") # Define the regex pattern with {n} syntax to match exactly 5 digits set(regex_pattern "^[0-9]{5}$") # Use the string(REGEX MATCH) command to validate the input data if(input_data MATCHES ${regex_pattern}) message("Input data is valid") else() message("Input data is not valid") endif() |
In this example, the regex pattern "^[0-9]{5}$" will match input data that consists of exactly 5 digits. The string(REGEX MATCH) command is used to check if the input data matches the regex pattern, and a message will be printed based on the result.
You can customize the regex pattern with the {n} syntax to match different requirements for your input data validation.
How to use the {n} syntax of regex with cmake to match specific word boundaries?
To use the {n} syntax of regex with CMake to match specific word boundaries, you can use the following syntax:
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string(REGEX MATCH "\\<word\\>[[:alnum:]]{n}\\<" input_string result)
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In this example, "<word\>" is used to match the specific word boundary at the beginning of the word, "[[:alnum:]]{n}" is used to match n alphanumeric characters, and "<" at the end is used to match the specific word boundary at the end of the word.
You can adjust the regex pattern as needed to match different word boundaries or characters.
