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package bjc.dicelang.expr;
import bjc.utils.parserutils.TokenSplitter;
import java.util.LinkedList;
import java.util.List;
/**
* Implements the lexer for simple expression operations.
*
* @author Ben Culkin
*/
public class Lexer {
/*
* Spliter we use
*/
private TokenSplitter split;
/**
* Create a new expression lexer.
*/
public Lexer() {
split = new TokenSplitter();
split.addDelimiter("(", ")");
split.addDelimiter("+", "-", "*", "/");
}
/**
* Convert a string from a input command to a series of infix tokens.
*
* @param inp
* The input command.
* @param tks
* The token state
*
* @return A series of infix tokens representing the command.
*/
public Token[] lexString(String inp, Tokens tks) {
String[] spacedTokens = inp.split("[ \t]");
List<Token> tokens = new LinkedList<>();
for(String spacedToken : spacedTokens) {
String[] rawTokens = split.split(spacedToken);
for(String tok : rawTokens) {
tokens.add(tks.lexToken(tok, spacedToken));
}
}
return tokens.toArray(new Token[0]);
}
}
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