// Copyright 2014 The Bazel Authors. All rights reserved. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. package com.google.devtools.build.lib.syntax; import com.google.devtools.build.lib.util.SpellChecker; import java.io.IOException; import java.util.Set; import javax.annotation.Nullable; // TODO(bazel-team): For performance, avoid doing HashMap lookups at runtime, and compile local // variable access into array reference with a constant index. Variable lookups are currently a // speed bottleneck, as previously measured in an experiment. /** * Syntax node for an identifier. * *
Unlike most {@link ASTNode} subclasses, this one supports {@link Object#equals} and {@link
* Object#hashCode} (but note that these methods ignore location information). They are needed
* because {@code Identifier}s are stored in maps when constructing {@link LoadStatement}.
*/
public final class Identifier extends Expression {
private final String name;
public Identifier(String name) {
this.name = name;
}
/**
* Returns the name of the Identifier.
*/
public String getName() {
return name;
}
public boolean isPrivate() {
return name.startsWith("_");
}
@Override
public void prettyPrint(Appendable buffer) throws IOException {
buffer.append(name);
}
@Override
public boolean equals(@Nullable Object object) {
if (object instanceof Identifier) {
Identifier that = (Identifier) object;
return this.name.equals(that.name);
}
return false;
}
@Override
public int hashCode() {
return name.hashCode();
}
@Override
Object doEval(Environment env) throws EvalException {
Object value = env.lookup(name);
if (value == null) {
throw createInvalidIdentifierException(env.getVariableNames());
}
return value;
}
@Override
public void accept(SyntaxTreeVisitor visitor) {
visitor.visit(this);
}
@Override
public Kind kind() {
return Kind.IDENTIFIER;
}
EvalException createInvalidIdentifierException(Set