dfc1234817
Rewrote REPL Added NIL and comments to parser. Added T as a predefined constant. Added HELP, TRACE, ENABLE-DEBUG-AST special form. Fixed variable evaluation (shouldn't automatically eval it's value)
30 lines
885 B
Java
Executable File
30 lines
885 B
Java
Executable File
package edu.utexas.cs345.jdblisp;
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/**
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* SExp
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* @author Jonathan Bernard (jdbernard@gmail.com)
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*/
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public interface SExp {
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/**
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* Evaluate this SExp within the context of the given SymbolTable.
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* @param table The SymbolTable context for this scope.
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* @return A SymbolTable containing the reutrn value.
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*/
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SExp eval(SymbolTable table) throws LispException;
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String display(String offset);
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public static final SExp T = new SExp() {
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public SExp eval(SymbolTable table) { return this; }
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public String display(String offset) { return offset + "T\n"; }
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public String toString() { return "T"; }
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};
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/*public static final SExp NIL = new SExp() {
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SExp eval(SymbolTable table) { return this; }
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String display(String offset) { return offset + "NIL\n"; }
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String toString() { return "NIL"; }
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};*/
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}
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