com.oracle.js.parser.ir.Statement Maven / Gradle / Ivy

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * The Universal Permissive License (UPL), Version 1.0
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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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package com.oracle.js.parser.ir;

/**
 * Statement is something that becomes code and can be stepped past. A block is made up of
 * statements. The only node subclass that needs to keep token and location information is the
 * Statement
 */
public abstract class Statement extends Node implements Terminal {

    private final int lineNumber;

    /**
     * Constructor
     *
     * @param lineNumber line number
     * @param token token
     * @param finish finish
     */
    public Statement(final int lineNumber, final long token, final int finish) {
        super(token, finish);
        this.lineNumber = lineNumber;
    }

    /**
     * Constructor
     *
     * @param lineNumber line number
     * @param token token
     * @param start start
     * @param finish finish
     */
    public Statement(final int lineNumber, final long token, final int start, final int finish) {
        super(token, start, finish);
        this.lineNumber = lineNumber;
    }

    /**
     * Copy constructor
     *
     * @param node source node
     */
    protected Statement(final Statement node) {
        super(node);
        this.lineNumber = node.lineNumber;
    }

    /**
     * Return the line number
     *
     * @return line number
     */
    public int getLineNumber() {
        return lineNumber;
    }

    /**
     * Is this a terminal statement, i.e. does it end control flow like a throw or return?
     *
     * @return true if this node statement is terminal
     */
    @Override
    public boolean isTerminal() {
        return false;
    }

    /**
     * Check if this statement repositions control flow with goto like semantics, for example
     * {@link BreakNode} or a {@link ForNode} with no test
     *
     * @return true if statement has goto semantics
     */
    public boolean hasGoto() {
        return false;
    }

    /**
     * Check if this statement has terminal flags, i.e. ends or breaks control flow
     *
     * @return true if has terminal flags
     */
    public final boolean hasTerminalFlags() {
        return isTerminal() || hasGoto();
    }

    /**
     * @return true if the completion value of this statement is never the value {@code empty}
     */
    public boolean isCompletionValueNeverEmpty() {
        return false;
    }
}