get_NoteGrammar

get_NoteGrammar

Gets Wave Note Grammar

Wave notes are a musical domain specific language.

Defining a Grammar streamlines how we can work with them.

Notes

Grammar Format

The Grammar is defined in a simple primal format:

It is an [Ordered] dictionary.

The order defines the order of precedence.

Each key is the name of an instruction.

Each value is one or more literal strings or [Regex]

The grammar is combined into a single regular expression, which is available in .NotePattern

Grammar Maturity

This Grammar is in currently in flux, and should not be viewed as final or fully matured.

Certain elements specified in the grammar are not yet supported:

• <> (Open/Close Phrase) support is not yet implemented
• [] (Open/Close Divide) only supports some partial syntax
• 𝆱𝆲 (GlissandoUp/Down) are not yet implemented

View Source

<#
.SYNOPSIS
    Gets Wave Note Grammar
.DESCRIPTION
    Wave notes are a musical domain specific language.

    Defining a Grammar streamlines how we can work with them.
.NOTES
    ### Grammar Format

    The Grammar is defined in a simple primal format:

    It is an `[Ordered]` dictionary.

    The order defines the order of precedence.
    
    Each key is the name of an instruction.

    Each value is one or more literal strings or `[Regex]`

    The grammar is combined into a single regular expression,
    which is available in `.NotePattern`

    ### Grammar Maturity

    This Grammar is in currently in flux, 
    and should not be viewed as final or fully matured.

    Certain elements specified in the grammar are not yet supported:

    * `<>` (Open/Close Phrase) support is not yet implemented
    * `[]` (Open/Close Divide) only supports some partial syntax
    * `𝆱𝆲` (GlissandoUp/Down) are not yet implemented
#>


[Ordered]@{
    OpenPhrase = '<'
    ClosePhrase = '>'
    OpenDivide = '['
    CloseDivide = ']'    
    UpTempo = '++'
    DownTempo = '--'
    Time1_1 = '𝅝'
    Time1_2 = '𝅗𝅥'
    Time1_4 = '𝅘𝅥'
    Time1_8 = '𝅘𝅥𝅮'
    Time1_16 = '𝅘𝅥𝅯'
    Time1_32 = '𝅘𝅥𝅰'
    Time1_64 = '𝅘𝅥𝅲'
    Time1_128 = '𝅘𝅥𝅲'
    GlissandoUp = '𝆱'
    GlissandoDown = '𝆲'    
    Rest1_1 = '𝄻'
    Rest1_2 = '𝄼'
    Rest1_4 = '𝄽'
    Rest1_8 = '𝄾'
    Rest1_16 = '𝄿'
    Rest1_32 = '𝅀'    
    Rest1_64 = '𝅁'
    Multiply = [Regex]::new('\*(?<scale>[\d\.]+)')
    Divide = [Regex]::New('/(?<scale>[\d\.]+)')
    RatioTime = [Regex]::New('\:(?<scale>[\d\.]+)')
    Repeat = [Regex]::New('!(?<scale>[\d+])')
    DECPS = [regex]::new('
        (?<decSequence>
            \e\[
            (?<decVolume>[0-7]);
            (?<decDuration>\d+);
            (?:
                (?<decNote>\d+
            );?){1,}
            ,~
            [\s\r\n]{0,}
        ){1,}',
        'IgnoreCase,IgnorePatternWhitespace'
    )    
    Emoji = [Regex]::new("[\p{IsHighSurrogates}\p{IsLowSurrogates}\p{IsVariationSelectors}\p{IsCombiningHalfMarks}]+")    
    AtTime = [Regex]::new('\@(?<scale>[\d\.]+)')
    Rest = [Regex]::new('
        (?>
            ~|            # Strudel notation            
            rest|silence| # Common english
            [xz]|         # ABC notation
            ø             # Notemoji notation
        )
    ','IgnoreCase,IgnorePatternWhitespace')
    BeepCommand = [Regex]::new('
        Beep                   # beep
        (?<beepSequence>
            (?:-n)?            # Followed by an option -n (new beat)
            \s{1,}             # and at least one space
            (?>
                -f\s{0,}(?<beepFrequency>[\d\.]+)\s{1,}
                |
                -l\s{0,}(?<beepDuration>[\d\.]+)\s{1,}
                |
                -d\s{0,}(?<beepDelay>[\d\.]+)\s{1,}
                |
                -r\s{0,}(?<beepRepeat>\d+)\s{1,}
            ){1,}
        ){1,}        
    ','IgnoreCase,IgnorePatternWhitespace')
    Beep = [Regex]::new(
        '
        Beep                   # Beep
        \s{0,}                 # Followed by optional whitespace
        \p{Ps}?                # Optional starting punctuation
        (?<frequency>[\d\.]+)  # Frequency
        \s{0,}                 # Optional whitespace
        \p{P}                  # Intermedia punctuation
        \s{0,}                 # Optional whitespace
        (?<duration>[\d\.]+)   # Duration
        \s{0,}                 # Optional whitespace
        \p{Pe}                 # Ending punctuation
        ',
        'IgnoreCase,IgnorePatternWhitespace'
    )
    MidiNote = [Regex]::New(
        '
        (?>
            # Prefixed midi note
            m(?:idi)?\s{0,}(?<midiNumber>\-?[\d\.]+)
            |
            # Suffixed midi note
            (?<midiNumber>\-?[\d\.]+)m(?:idi)?\s{0,}
        )
        ',
        'IgnoreCase,IgnorePatternWhitespace'
    )    
    ExactFrequency = [Regex]::new(
        '(?>
            (?<frequency>\-?\d+(\.\d+)?)(?<unit>(?>hz|㎐))
            |
            (?<unit>(?>hz|㎐))(?<frequency>\-?\d+(\.\d+)?)
        )',        
        'IgnoreCase,IgnorePatternWhitespace'
    )
    Sleep = [Regex]::new(
        '
        Sleep                  # Sleep
        \s{0,}                 # Followed by optional whitespace
        \p{Ps}?                # Optional starting punctuation
        \s{0,}                 # Optional whitespace
        (?<duration>[\d\.]+)   # Duration
        \s{0,}                 # Optional whitespace        
        \p{Pe}?                # Optional ending punctuation',
        'IgnoreCase,IgnorePatternWhitespace'
    )
    # Letter notes are one of the more challenging parts of the grammar
    # We only want to match letters within words that are all notes.
    LetterNote = [Regex]::new('
    # Do not match if we preceed a letter 
    # or punctuation that is not a-g
    # followed by any number of a-g letters
    (?<![\p{L}\p{P}-[abcdefg\|\,\.]][abcdefg\|]{0,})
    (?<pitch>
        (?>
            (?<flat>[\u266d_])
            |
            (?<sharp>[\#\u266f\^])
        )
    )?
    (?<letter>[a-g]) # a letter between a and g
    # as long as the next character is not a letter and not a-g or s.
    (?![\p{L}-[abcdefgs]])
    (?: 
        # Then an optional flat/sharp alter
        # and a number
        (?>
            # If it is a `b` flat, 
            # it has to be followed by an octave.
            (?<flat>b)
                (?<octave>[1-8])
            |            
            # If it is a notemoji flat or underscore
            (?<flat>[\u266d_])
                # the octave is optional
                (?<octave>[1-8])?
            |
            # If it is a notemoji sharp, pound sign, caret, or s
            (?<sharp>[\#\u266f\^s])
                # the octave is optional
                (?<octave>[1-8])?
            |
            # If there was no sharp or flat, the octave can still be present
            (?<octave>[1-8])
        )
    )?
     # an optional octave
    ', 'IgnoreCase, IgnorePatternWhitespace'        
    )

    Range = [Regex]::New('\.\.')

    Combine = [Regex]::New(',')
    Decimal = [Regex]::new(
    '
-?[\d\.]+(?:E[\+\-]\d+)?
    ', 'IgnoreCase')

    
}