# IT:AD:TinyPG:HowTo #



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## Process ##


## Define a grammar.

* Open the app, 
* Write a grammar.
    * A grammar is defined as a extended-BNF notation file of `terminal` and `non-terminal` symbols.

Example of `terminal symbols`:


    BOOLEANLITERAL    -> @"true|false";
    DECIMALINTEGERLITERAL-> @"[0-9]+(UL|Ul|uL|ul|LU|Lu|lU|lu|U|u|L|l)?";
    REALLITERAL         -> @"([0-9]+\.[0-9]+([eE][+-]?[0-9]+)?([fFdDMm]?)?)|(\.[0-9]+([eE][+-]?[0-9]+)?([fFdDMm]?)?)|([0-9]+([eE][+-]?[0-9]+)([fFdDMm]?)?)|([0-9]+([fFdDMm]?))";
    HEXINTEGERLITERAL    -> @"0(x|X)[0-9a-fA-F]+";
    STRINGLITERAL        -> @"\""(\""\""|[^\""])*\"""; // shortcut implementation, not quite ready
    FUNCTION        -> @"[a-zA-Z_][a-zA-Z0-9_]*(?=\s*\()"; // matches only when followed by (
    VARIABLE        -> @"[a-zA-Z_][a-zA-Z0-9_]*(?!\s*\()"; // matches only when NOT followed by (
    CONSTANT        -> @"(?i)pi|e";
    BRACEOPEN        -> @"{\s*";
    BRACECLOSE        -> @"\s*}";
    BRACKETOPEN        -> @"\(\s*";
    BRACKETCLOSE        -> @"\s*\)";
    SEMICOLON        -> @";";
    PLUSPLUS        -> @"\+\+";
    MINUSMINUS        -> @"--";
    PIPEPIPE        -> @"\|\|";
    AMPAMP            -> @"&&";
    AMP            -> @"&(?!&)"; // matches only when NOT followed by second &
    POWER            -> @"\^";
    PLUS            -> @"\+";
    MINUS            -> @"-";
    EQUAL            -> @"==";
    ASSIGN            -> @"=";
    NOTEQUAL        -> @"!=|<>";
    NOT            -> @"!";
    ASTERIKS        -> @"\*";
    SLASH            -> @"/";
    PERCENT        -> @"%";
    QUESTIONMARK        -> @"\?";
    COMMA            -> @",";
    LESSEQUAL        -> @"<=";
    GREATEREQUAL        -> @">=";
    LESSTHAN        -> @"<(?!>)"; // matches only when not followed by >
    GREATERTHAN        -> @">";
    COLON            -> @":";
    EOF            -> @"^$";

    [Skip] WHITESPACE     -> @"\s+";