org.jatha.machine
Class opSEL

java.lang.Object
  org.jatha.dynatype.StandardLispValue
      org.jatha.compile.LispPrimitive
          org.jatha.machine.SECDop
              org.jatha.machine.opSEL

All Implemented Interfaces:

Comparable, LispValue

 class opSEL
extends SECDop

opSEL takes a branch in an IF-ELSE expression. It selects code from the C register and, depending on whether the topmost value in the S register is true or not, places that code on the C register and pushes the remaining C register code onto the D register. Pops the S register.

See Also:

SECDMachine

Field Summary

Fields inherited from class org.jatha.compile.LispPrimitive

functionName, functionNameSymbol, inlineP, maxNumberOfArgs, minNumberOfArgs

Fields inherited from class org.jatha.dynatype.StandardLispValue

f_lisp

Constructor Summary

opSEL(Jatha lisp)
It calls SECDop() with the machine argument and the label of this instruction.

Method Summary

void	Execute(SECDMachine machine) Execute performs the operation using the abstract machine registers.
LispValue	grindef(LispValue code, int indentAmount)

Methods inherited from class org.jatha.machine.SECDop

getComponentAt, loc, setComponentAt, setLoc, toString

Methods inherited from class org.jatha.compile.LispPrimitive

basic_functionp, CompileArgs, CompileArgs, indent, internal_prin1, internal_princ, internal_print, LispFunctionNameString, LispFunctionNameSymbol, parameterCountString, printCode, printCode, validArgumentList

Methods inherited from class org.jatha.dynatype.StandardLispValue

abs, acos, add, adjustSpecialCount, append, apply, apropos_print, asin, assoc, atan, atan2, atom, basic_atom, basic_bignump, basic_consp, basic_constantp, basic_floatp, basic_foreignp, basic_integerp, basic_keywordp, basic_length, basic_listp, basic_macrop, basic_null, basic_numberp, basic_stringp, basic_symbolp, bignump, boundp, butlast, car, cdr, ceiling, characterp, clrhash, compareTo, concatenate, consp, constantp, contains, copy_list, copy, cos, cot, csc, degreesToRadians, divide, documentation, eighth, elt, elt, eq, eql, equal, equalNumeric, factorial, fboundp, fifth, first, floatp, floor, fourth, funcall, functionp, get_specialCount, gethash, gethash, getLisp, greaterThan, greaterThanOrEqual, hash_table_count, hash_table_rehash_size, hash_table_rehash_threshold, hash_table_size, hash_table_test, hashtablep, integerp, internal_getName, internal_prin1_as_cdr, internal_princ_as_cdr, internal_print_as_cdr, iterator, keywordp, last, length, lessThan, lessThanOrEqual, lisp_null, list, listp, max, member, min, multiply, nconc, negate, neql, ninth, nreverse, nstringCapitalize, nstringDowncase, nstringUpcase, numberp, pop, position, prin1, princ, print, push, radiansToDegrees, rassoc, readFromString, reciprocal, remhash, remove, rest, reverse, rplaca, rplacd, sec, second, set_special, setf_documentation, setf_gethash, setf_symbol_function, setf_symbol_plist, setf_symbol_value, setLisp, setPackage, setq, seventh, showStackTrace, sin, sixth, specialP, sqrt, string, stringCapitalize, stringDowncase, stringEndsWith, stringEq, stringEqual, stringGreaterP, stringGreaterThan, stringGreaterThanOrEqual, stringLeftTrim, stringLeftTrim, stringLessP, stringLessThan, stringLessThanOrEqual, stringNeq, stringNotGreaterP, stringNotLessP, stringp, stringRightTrim, stringRightTrim, stringStartsWith, stringTrim, stringTrim, stringUpcase, subst, substring, substring, subtract, symbol_function, symbol_name, symbol_package, symbol_plist, symbol_value, symbolp, tan, tenth, third, toCollection, toJava, toJava, toString, toStringAsCdr_internal, toStringAsCdr, toStringShort, toStringShort, toStringSimple, type_of, typep, uses, zerop

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

opSEL

public opSEL(Jatha lisp)

It calls SECDop() with the machine argument and the label of this instruction.

See Also:

SECDMachine

Method Detail

Execute

public void Execute(SECDMachine machine)

Description copied from class: LispPrimitive

Execute performs the operation using the abstract machine registers. Arguments are found on the S register stack, in reverse order. UNLIMITED argument lists are collected into a list which is the top element on the stack. The implementation should pop an appropriate number of arguments from the stack, perform a computation, then push a result back on the S stack. The instruction should then be popped from the C (code) register. A LispValueFactory objects is available in the static variable LispValueFactory. Example implementations:

   FIRST
   class FirstPrimitive extends LispPrimitive
   {
     public First()
     {
       super("FIRST", 1);   // 1 argument
     }

     public void Execute(SECDMachine machine)
     {
       LispValue arg = machine.S.pop();

       machine.S.push(my_first(arg));
       machine.C.pop();
     }
   }
 

A multi-argument function must pop the arguments in reverse order.

     public void Execute(SECDMachine machine)
     {
       LispValue arg2 = machine.S.pop();
       LispValue arg1 = machine.S.pop();

       machine.S.push(my_new_function(arg1, arg2));
       machine.C.pop();
     }
   }
 

To register the new primitive, call:

    Jatha.COMPILER.Register(new FirstPrimitive());
 

Specified by:

Execute in class LispPrimitive

Parameters:

machine - The abstract machine instance.

See Also:

LispCompiler

grindef

public LispValue grindef(LispValue code,
                         int indentAmount)

Overrides:

grindef in class LispPrimitive