CLIHelper is a simple lightweight library aimed at easing the pain of building command-line interfaces and read-eval-print loops by providing user input and argument capturing functions.
CLIHelper works by simply scanning and lexing strings in-place with the help of the C++ standard library.
At its core, CLIHelper is a lexer and uses the concept of fields (which can also be thought of as tokens)
A field is simply a substring that contains no spaces.
"plant" | a field
"Literary" | another field
When a field contains a space character, it becomes two fields.
"lucid imagination" | a string containing two fields
Space characters only serve to separate fields; if one or more space characters appear at either the beginning or end of a field, CLIHelper ignores them.
" snail "
"snail" | these are the same to CLIHelper
Non-alphanumeric characters are treated the same as alphanumeric characters.
"lucid + snail" | three distinct fields: "lucid" "+" "snail"
Using these concepts, you can parse user input strings like:
romdump -WHOLE -v --checksum
with no problem at all.
//Returns the contents of stream up to, but excluding the newline character.
std::string readInput(std::istream &stream = std::cin);
//Returns true if there are no fields in the line or false
//if the line has at least one field.
bool allFieldsEmpty(const std::string &line);
//Returns the number of fields in the line.
unsigned int fieldCount(const std::string &line);
//Returns true if the field at index matches the key,
//returns false otherwise
//
// fieldCount(line) > 0
// 0 <= index < fieldCount(line)
bool fieldIs(const std::string &key, size_t index, const std::string &line);
//Returns the field at index in the line.
//
// fieldCount(line) > 0
// 0 <= index < fieldCount(line)
std::string grabField(size_t index, const std::string &line);