This works: sage: *for* i *in* [ZZ,QQ,RR]:
....: print('empty string in',i,':','' *in* i) ....: empty string in Integer Ring : False empty string in Rational Field : False empty string in Real Field with 53 bits of precision : False This gives an error: sage: '' *in* CC […] ^ SyntaxError: invalid syntax Why? TIA, Guillermo -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-support/CANnG189my7k1HMw8FGrkDN2Roxr0e36PC4tB32ZYEWKPC_prmQ%40mail.gmail.com.