#!/usr/bin/env python
from ply import lex, yacc
# Tokenize (lex)
tokens = (
"NOTE_LENGTH",
"BASENOTE",
"ACCIDENTAL",
"REST",
"OCTAVE",
"CHORD_TYPE",
)
t_BASENOTE = r"[A-Ga-g]"
t_ACCIDENTAL = r"\^{1,2}|_{1,2}|="
t_REST = r"z"
t_OCTAVE = r"'+|,+"
t_CHORD_TYPE = r"m|7|m7|0|o|\+|mb5|sus|sus4|maj7|mmaj7|7sus4|dim|dim7|7b5|m7b5|6|b6|m6|mb6|46|maj9|9|add9|7b9|m9"
def t_NOTE_LENGTH(t):
r"/?\d+"
multiplier = float(t.value.strip("/"))
if t.value.startswith("/"):
multiplier = 1/multiplier
t.value = multiplier
return t
def t_error(t):
raise TypeError("Unknown text '%s'" % (t.value,))
t_ignore = " |"
lex.lex()
#lex.input("GFG B'AB,, | g/2fg gab | GFG BAB | d2A AFD")
s = "GFG B'AB,, | g/2fg gab | GFG BAB | d2A AFD"
#s = "GF_G,/2"
lex.input(s)
for tok in iter(lex.token, None):
print repr(tok.type), repr(tok.value)
# Parse (yacc)
class Note(object):
def __init__(self, value, duration=.25, octave=8):
self.value = value
self.duration = duration
self.octave = octave
self.accidental = None
def __repr__(self):
return "Note %s %s %s" % (self.value, self.duration, self.octave)
#def p_element(p):
# "element : note_element"
# p[0] = p[1]
#
#def p_note_element(p):
# '''note_element : note_element note_stem
# | note_stem
# '''
# p[0] = p[1]
#
#def p_note_stem(p):
# '''note_stem : note'''
# p[0] = p[1]
#
#def p_note(p):
# '''note : note_or_rest
# | note_or_rest NOTE_LENGTH
# '''
# p[0] = p[1]
#
#def p_note_or_rest(p):
# '''note_or_rest : pitch
# | REST
# '''
# p[0] = p[1]
#
#def p_pitch(p):
def p_pitch_list(p):
'''score : score note
'''
p[0] = p[1] + [p[2]]
def p_score(p):
'''score : note
'''
p[0] = [p[1]]
def p_note(p):
'''note : pitch
'''
p[0] = p[1]
def p_note_length(p):
''' note : note NOTE_LENGTH
'''
new_note = p[1]
new_note.duration = p[2]
p[0] = new_note
def p_accidental(p):
'''pitch : ACCIDENTAL pitch
'''
p[2].accidental = p[1]
p[0] = p[2]
def p_octave(p):
'''pitch : pitch OCTAVE
'''
count = len(p[2])
increment_or_decrement = 1 if p[2][0] == "," else -1
octave = 8 + (count * increment_or_decrement)
p[1].octave = octave
p[0] = p[1]
def p_pitch(p):
'''pitch : BASENOTE
'''
p[0] = Note(p[1])
def p_error(p):
print "Syntax error at '%s' of element type %s" % (p.value, p.type)
yacc.yacc()
#print yacc.parse("GFG B'AB,, | g/2fg gab | GFG BAB | d2A AFD")
print yacc.parse(s)