Macros that work in Pig 0.11 fail in Pig 0.12 :(

http://my.safaribooksonline.com/book/databases/9781449326890/7dot-exploring-data-with-reports/i_sect13_id196600_html

The ntf-idf macro listed there works under 0.11. Under 0.12, it results in this:

13/12/16 22:09:19 INFO pig.ExecTypeProvider: Trying ExecType : LOCAL
2013-12-16 22:09:19,159 [main] INFO org.apache.pig.Main - Apache Pig version 0.13.0-SNAPSHOT (rUnversioned directory) compiled Dec 09 2013, 14:37:29
2013-12-16 22:09:19,159 [main] INFO org.apache.pig.Main - Logging error messages to: /private/tmp/pig_1387260559120.log
2013-12-16 22:09:19.268 java[38060:1903] Unable to load realm info from SCDynamicStore
2013-12-16 22:09:19,528 [main] INFO org.apache.pig.backend.hadoop.executionengine.HExecutionEngine - Connecting to hadoop file system at: file:///
2013-12-16 22:09:20,189 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1025:
at expanding macro 'tf_idf' (per_business.pig:9)
<file per_business.pig, line 35, column 17> Invalid field projection. Projected field [tf_idf] does not exist in schema: business_id:chararray,token:chararray,term_freq:double,num_docs_with_token:long.
2013-12-16 22:09:20,189 [main] ERROR org.apache.pig.tools.grunt.Grunt - org.apache.pig.impl.plan.PlanValidationException: ERROR 1025:
at expanding macro 'tf_idf' (per_business.pig:9)
<file per_business.pig, line 35, column 17> Invalid field projection. Projected field [tf_idf] does not exist in schema: business_id:chararray,token:chararray,term_freq:double,num_docs_with_token:long.
at org.apache.pig.newplan.logical.expression.ProjectExpression.findColNum(ProjectExpression.java:191)
at org.apache.pig.newplan.logical.expression.ProjectExpression.setColumnNumberFromAlias(ProjectExpression.java:174)
at org.apache.pig.newplan.logical.visitor.ColumnAliasConversionVisitor$1.visit(ColumnAliasConversionVisitor.java:53)
at org.apache.pig.newplan.logical.expression.ProjectExpression.accept(ProjectExpression.java:215)
at org.apache.pig.newplan.DependencyOrderWalker.walk(DependencyOrderWalker.java:75)
at org.apache.pig.newplan.PlanVisitor.visit(PlanVisitor.java:52)
at org.apache.pig.newplan.logical.optimizer.AllExpressionVisitor.visit(AllExpressionVisitor.java:142)
at org.apache.pig.newplan.logical.relational.LOInnerLoad.accept(LOInnerLoad.java:128)
at org.apache.pig.newplan.DependencyOrderWalker.walk(DependencyOrderWalker.java:75)
at org.apache.pig.newplan.logical.optimizer.AllExpressionVisitor.visit(AllExpressionVisitor.java:124)
at org.apache.pig.newplan.logical.relational.LOForEach.accept(LOForEach.java:76)
at org.apache.pig.newplan.DependencyOrderWalker.walk(DependencyOrderWalker.java:75)
at org.apache.pig.newplan.PlanVisitor.visit(PlanVisitor.java:52)
at org.apache.pig.PigServer$Graph.compile(PigServer.java:1694)
at org.apache.pig.PigServer$Graph.compile(PigServer.java:1686)
at org.apache.pig.PigServer$Graph.access$200(PigServer.java:1387)
at org.apache.pig.PigServer.execute(PigServer.java:1302)
at org.apache.pig.PigServer.executeBatch(PigServer.java:391)
at org.apache.pig.PigServer.executeBatch(PigServer.java:369)
at org.apache.pig.tools.grunt.GruntParser.executeBatch(GruntParser.java:133)
at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:195)
at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:166)
at org.apache.pig.tools.grunt.Grunt.exec(Grunt.java:84)
at org.apache.pig.Main.run(Main.java:600)
at org.apache.pig.Main.main(Main.java:156)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.util.RunJar.main(RunJar.java:156)