in-delimiter - Search in a String with One to Three Delimiters (No Regex)

• in-delimiter - Search in a String with One to Three Delimiters (No Regex)
  • Features
  • Overview
  • Case Examples and Usage
    • Full Example: Different Outer Delimiters and Inner Delimiters
    • Simplified Example: Same Outer Delimiter and Optional Inner Delimiter
  • Contributing
  • License

Features

• Zero Regular Expressions
• Zero dependencies
• Single, short, and simple function
• Up to three delimiters (begin, end, and inner) can be given, and can be returned as part of output
• Heavily tested (almost 30 cases)

Overview

The primary motivation for this is CMake syntax analysis (this can be seen in the test cases).

It's incredibly cumbersome to use Regex in a situation like this, especially in languages like CMake which use $ or other reserved characters in Regex. Alternate ways like splitting the string will destroy the syntax and/or just leave you with garbage on top of garbage.

Case Examples and Usage

Full Example: Different Outer Delimiters and Inner Delimiters

Consider the following syntactically correct CMake snippet:

if($<$<OR:$<CXX_COMPILER_ID:MSVC>,$<CXX_COMPILER_ID:Clang>>>)
# ...
endif()

Assume we want to get the OR segment with its associated delimiters. With this function, it is:

let line = "if($<$<OR:$<CXX_COMPILER_ID:MSVC>,$<CXX_COMPILER_ID:Clang>>>)";
let result = getStringWithinDelimiters(line, line.indexOf("OR"), "$<", ">", true, ":");

// result now has "$<OR:$<CXX_COMPILER_ID:MSVC>,$<CXX_COMPILER_ID:Clang>>"

Assume we want only the inner delimiter : with the above result:

let line = "if($<$<OR:$<CXX_COMPILER_ID:MSVC>,$<CXX_COMPILER_ID:Clang>>>)";
let result = getStringWithinDelimiters(line, line.indexOf("OR"), "$<", ">", false, ":", true);

// result now has "OR:$<CXX_COMPILER_ID:MSVC>,$<CXX_COMPILER_ID:Clang>"

Simplified Example: Same Outer Delimiter and Optional Inner Delimiter

A simplified function with only one delimiter and optional inner delimiter is also provided.

Consider the following C++ code:

#include <iostream>
#include <vector>

int main()
{
    std::vector<int> v = { 7, 8, 9 };

    std::cout << "Vector size: " << v.size() << std::endl();
    // ...
}

Assume we want "Vector size: ":

let line = "std::cout << \"Vector size: \" << v.size() << std::endl();";
let del = "<<";
let result = getStringWithinSurroundDelimiter(line, line.indexOf("size:"), del);

// result now has " \"Vector size: \" "

Assume we want to get the size() function:

let line = "std::cout << \"Vector size: \" << v.size() << std::endl();";
let del = "<<";
let result = getStringWithinSurroundDelimiter(line, line.indexOf(".") + 1, del, ".");

// result now has "size() "

Note that in any of these cases, if the input is invalid or there was nothing found, the return value will always be null.

Contributing

PRs are welcome.

Create a branch against master and have the branch name be descriptive.

Before submitting, ensure that all tests pass and there are no linting errors.

License

MIT