How to Use the {N} Syntax Of Regex With Cmake?

To use the {n} syntax of regex with CMake, you can specify the number of occurrences of the preceding element that you are searching for. For example, if you want to find a specific word that appears exactly three times in a string, you would use the syntax {3} after the word in your regex pattern. This allows you to define the exact number of repetitions of a specific element that you are looking for in CMake's regex operations.

How to use the {n} syntax of regex with cmake for capturing a specific number of groups?

To use the {n} syntax of regex with CMake for capturing a specific number of groups, you can use the following syntax in the CMake script:

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string(REGEX MATCH "pattern1 pattern2" output ${input})

In this example, the {n} syntax for capturing a specific number of groups is not explicitly specified in the CMake script. Instead, the desired number of groups is determined by the regular expression pattern used in the string(REGEX MATCH ...) command.

The regular expression pattern should be written in a way that it captures the specific number of groups you need. The {n} syntax can be used in the regular expression pattern to specify the exact number of groups to be captured.

For example, if you want to capture exactly three groups of digits from an input string, you can use the following regular expression pattern in the string(REGEX MATCH ...) command:

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string(REGEX MATCH "([0-9]+) ([0-9]+) ([0-9]+)" output ${input})

In this pattern, the {n} syntax is used to specify three groups of digits to be captured. The regular expression will match the input string and capture three groups of digits separated by spaces.

Make sure to adjust the regular expression pattern according to your specific requirements to capture the desired number of groups with the {n} syntax in CMake.

What is the significance of the {n} syntax in regex with cmake?

In regex syntax, the curly braces with a number inside ({n}) represent a quantifier that specifies the exact number of occurrences of the preceding element. In CMake regex, the {n} syntax can be used in the MATCHES keyword to match a string that contains exactly n occurrences of a specific pattern. This can help in specifying more strict matching criteria in regex patterns within CMake scripts.

How to use the {n} syntax of regex with cmake for defining specific occurrences?

To use the {n} syntax of regex with CMake for defining specific occurrences, you can use the MATCHES operator in an IF statement. Here is an example of how you can use the {n} syntax in CMake:

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# Define the input string
set(input_string "abc123def456ghi")

# Check if the input string contains exactly 3 digits
if(input_string MATCHES ".*[0-9]{3}.*")
    message("Input string contains exactly 3 digits")
else()
    message("Input string does not contain exactly 3 digits")
endif()

In this example, the regex pattern ".[0-9]{3}." is used to match any sequence of characters that contains exactly 3 digits. The MATCHES operator in the IF statement is used to check if the input string matches the specified pattern.

You can customize the regex pattern and the {n} syntax to match specific occurrences or patterns in your input string.