Grill Tag interpreter in Python (~92bytes)

grilltag.py

# Grill Tag interpreter in Python with datastring viewer argument o=:
# https://esolangs.org/wiki/Grill_Tag
# _p_roductions (standard RLE * 2), _d_atastring: {-1: '1', 0: '0', n*2: '01'*n + '0'}
def gtag(p,d,o=print,c=0):
 while d:o(d);d+=[p[c%len(p)]]*(d[0]&1);d[0]-=1;d=d[d[0]<0:];c+=1

usage.py

from grilltag import gtag

"""Usage Examples:"""
# Using this interpreter's own custom RLE (standard * 2): Equivalent to: ([0,1,1], "110110")
gtag([0, 2, 2], [-1, -1, 0, -1, -1, 0])

# With internal datastring representation output as binary:
gtag([0, 2, 2], [-1, -1, 0, -1, -1, 0], lambda s: print(''.join(['1' if v<0 else ('01'*((v+1)//2)+'0')[v&1:] for v in s])))

# Convert standard RLE and initial strings as arguments, with binary output: 
gtag([v*2 for v in [0, 1, 1]], [-int(b) for b in "110110"], lambda s: print(''.join(['1' if v<0 else ('01'*((v+1)//2)+'0')[v&1:] for v in s])))