
[Syntax error - subterm missing?
 You could have read something like 'foo()' or '(3+)'
 The context is:   ]
                                                                                                                                               
[Syntax error - missing closing bracket
 You could have had something like 'foo(a,b,c.' or '[A,..C.'
 The context is:   ]
                                                                                                                                 
                                                                                                                                                                                                                                                              
[Syntax error - restarting list after '|' or ',..'
 Only one term can appear after one of these (the 'rest' of the list).
 Something like '[a,b,..c,d]' is wrong.
 The context is:   ]
                                                                   
[Syntax error - missing comma or operator?
 Perhaps you have missed out an operator declaration.
 Eg 'a b c', '[A B]' and 'f (a)' are wrong.
 The context is:   ]
                                                                                        
[Syntax error - there are too many closing brackets.
 Eg 'f(a,b))' and 'f([a,b,C])]' are wrong.
 The context is:   ]
                                                                                                                                      
                                                                                                                                                                                                                                                              
[Syntax error - an unexpected character has appeared after ',.'.
 This sequence must be followed by another '.'
 The context is:   ]
                                                                                                                      
[Syntax error - ',..' has been read elsewhere than in a list.
 Eg 'f(a,b,..c)' and 'a :- b,..c.' are wrong.
 The context is:   ]
                                                                                                                          
                                                                                                                                                                                                                                                              
[Syntax error - a closing bracket does not match the corresponding opening
 one. Thus 'f(a,b]' and '[a,b,c)' are wrong.
 The context is:   ]
                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
[Error - illegal file name.
 The arguments to 'see', 'tell' and other predicates that manipulate
 files should be atoms]
                                                                                                                                  
                                                                                                                                                                                                                                                              
[Error - over-complex variable names.
 There is only a small amount of space for storing variable names during
 reading, and this can be exhausted if there are many variables or long
 variable names]
                                                  
[Error - adding to system predicates.
 It is not allowable to add new clauses for predicates that have a special
 significance to the system (eg 'trace', 'see')]
                                                                                         
[Error - out of io channels.
 There are only 16 IO channels allowed, and all are
 presently allocated]
                                                                                                                                                    
[Error - 'op' first argument.
 The first argument to 'op' must be an operator precedence - an integer
 between 0 and 255]
                                                                                                                                 
[Error - 'op' second argument.
 The second argument to 'op' should be an operator type - one of
 'xf', 'fx', 'xfx', 'xfy' and 'yfx']
                                                                                                                      
[Error - 'op' third argument.
 The third argument to 'op' should be the atom being
 declared as an operator]
                                                                                                                                              
[Error - functor arity limit.
 You have attempted to create a functor with arity greater than 15.
 This is not possible with this PROLOG implementation]
                                                                                                  
[Error - atom name limit.
 You have attempted to create an atom whose name has more than about
 255 characters. This is not possible in RT-11 PROLOG]
                                                                                                     
[Error - variable goal.
 You have invoked a variable goal without the variable being properly
 instantiated. Every PROLOG goal must have its predicate known]
                                                                                             
[Error - bad arithmetic expression.
 An arithmetic expression (2nd argument to 'is', argument to 'put', '<' etc)
 must consist solely of integers and the functors _ * _, _ + _,  things to
 _ - _, _ / _, _ mod _, [_]]
                                 
[Error - 'is' first argument.
 The first argument to 'is' must be an integer or an
 uninstantiated variable]
                                                                                                                                              
[Error - 'assert' argument.
 Something to be asserted must be a valid clause, and not an
 integer or uninstantiated variable, for instance]
                                                                                                               
[Error - graphics predicate error -
The fields need integers, expressions, variables or
atoms like 'up', 'down', 'left', 'right', 'on', 'off'.]
                                                                                                           
[Error - invalid list of vertices.
The list must consist of form [[a,b], ... [c,d]] with
3 - 16 vertices and a,b,c,d etc integers.]
                                                                                                                       
                                                                                                                                                                                                                                                              
[Error - bad list.
 Various system predicates (ie 'name') sometimes expect finite
 lists as arguments. You have provided an illegal one (perhaps it
 doesn't end in [])]
                                                                                 
                                                                                                                                                                                                                                                              
[Error - name arguments
 The first argument to 'name' must unify with an atom and the
 second argument with a list of integers. Also, if the first is
 an uninstantiated variable then the second must be ground]
                                        
                                                                                                                                                                                                                                                              
[Error - 'deny' arguments.
 'deny' must take 2 arguments specifying the head and body of a clause.
 'retract' must match a clause as a whole. 'retractall' must match a clause
 head. All predicates must be instantiated]
                               
[Error - accessing system clauses.
 It is illegal to look at or remove clauses for system predicates]
                                                                                                                                                      
                                                                                                                                                                                                                                                              
[Error - end of file
 You have tried to read on after the end of a file. You may have failed to
 close a string or quoted atom . The file will be closed if it is
 not the tty]
                                                                          
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                              
[Error - invalid graphics call
  This version on the RT-11 PROLOG system doesn't have graphics.]
                                                                                                                                                           
[Error - division by 0
 If this were done, the machine would not be big enough to hold the answer]
                                                                                                                                                         
[Error - bad arguments to 'ancestor'
 The predicate 'ancestor' must only be called with an integer as its
 first argument and an uninstantiated variable as its second]
                                                                                   
[Error - too many atoms
 PROLOG only allows each PROLOG process to have available 1024
 different atoms. You can't really continue after this error.]
                                                                                                     
[Error - 'functor' first argument
 The first argument to 'functor' must be an atom, a complex term
 or an uninstantiated variable]
                                                                                                                        
[Error - functor second argument
 You have given a variable as the first argument, and so the
 second should have been an atom]
                                                                                                                           
[Error - file doesn't exist
 You have referred (in a 'see', 'consult' etc) to a file that does not
 exist or that you are not allowed to use in the operation requested.
]
                                                                               
[Error - cannot write
 For some reason (hardware?) you cannot write to the current output.
]
                                                                                                                                                              
[Error - cannot read
 For some reason (hardware?) you cannot read from the current input]
                                                                                                                                                                  
[Error - cannot close file
 For some reason (hardware?) it was not possible to successfully
 close a file]
                                                                                                                                                
[Error - functor third argument
 You have given 'functor' a variable as its first argument, and so the
 third argument should have been a valid arity (integer less than 16)]
                                                                             
[Error - 'arg' first argument
 The first argument to 'arg' must be a complex term]
                                                                                                                                                                         
[Error - 'arg' second argument
 The second argument to 'arg' must be an integer less than or equal to the
 arity of the first argument (and not 0)]
                                                                                                       
[Error - interpreter space exhausted.
 If the operation of an evaluable predicate like 'assert' or 'write'
 or unification gets into a loop or deeply nested, the interpreter
 can run out of space. You prob. have a very complex or circular term]
     
[Error - infinite loop.
 Your program has run out of space, and so is probably in an infinite
 loop. On the other hand it may just be too big, in which case you need
 to consider appropriate changes]
                                                  