aaaa, Prolog - rextester

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objeto:- write('{'),read(X), (X='atributo'->atributo),write('}').
a1:- read(X),(X='atributo'-> write(','),atributo;(X='fin'->write(''))).
atributo:- read(X), write('"'), write(X), write('":'),tipoatributo(X),a1. 
tipoatributo(M):- read(X), (X='metodo'->metodo(M); X='numero'->numero;  X='cadena'-> cadena ; X='objeto'->objeto; X='arreglo'-> arreglo;write('error')).
cadena:- read(X), write('"'), write(X), write('"').
numero:- read(X), write(X).
arreglo:- read(X),write('['),(X='elemento'->elemento), write(']').
ai:- read(X),(X='elemento'-> write(','),elemento;(X='fin'->write(''))).
elemento:- tipoatributo(''),ai.
metodo(M):- write('"function() {'),a2,write(' return '), write(M), write(';}"').
a2:- read(X), (X='decision'->decision; X='asignacion' -> asignacion; X='fin' -> write('');(write('ERROR: '),write(X))).
asignacion:- read(X), write(X), write('='), read(Y), write(Y), write(';'),a2.
decision:- write('if('),condicion,write(')'), verdadero, write('}'),falso,write('}').
condicion:- read(X), write(X).
verdadero:- write('{'),a2.
falso:- write('else {'),a2.
:-objeto.

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