Why Does My `ifstream::open()` Fail with 'No Matching Function' in Dev-C , But Not Visual Studio?

Understanding "No Matching Function - ifstream open() Error"

In the provided C code, the error "no matching function for call 'std::basic_ifstream::open(std::string&)' " arises from attempting to open a file using a string literal as an argument. This error occurs when compiling with dev cpp but not in VS, indicating platform-specific behavior.

Resolving the Error

To resolve the error, modify the file opening line as follows:

file.open(name.c_str());

Alternatively, you can use the constructor to both construct and open the file stream:

std::ifstream file(name.c_str());

In C 11 and later, support for opening a file using a std::string argument was introduced. However, older versions of C , as used by dev cpp, do not support this feature.

Additional Modifications

Besides the file opening fix, it's also recommended to:

• Pass the argument to loadNumbersFromFile() as a const reference using std::string const& to indicate that it will not be modified by the function.
• Use the ignore() method with the numeric_limits::max() value and a delimiter of 'n' to skip any leading whitespace and read only numerical values from the file.

The above is the detailed content of Why Does My `ifstream::open()` Fail with 'No Matching Function' in Dev-C , But Not Visual Studio?. For more information, please follow other related articles on the PHP Chinese website!