ANTLR3 throws internal error with java.lang.NullPointerException
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I tried to use ANTLR3 to build a simple Regexpression parser, but it throws the internal error
Here is the Sample.g
grammar Sample;
options {
memoize=true;
output=AST;
}
tokens {
RegExp;
}
RegExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$RegExpression.start, $RegExpression.text] $a+ )
;
fragment NL: 'n' | 'r';
ANY : . ;
I run the command:
java -jar antlr-3.5.2-complete.jar -print Sample.g
and it gives this:
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.DefineGrammarItemsWalker.rewrite_atom(DefineGrammarItemsWalker.java:3896)
...
...
Updated according to comments
grammar Sample{
memoize=true;
output=AST;
}
tokens {
RegExp;
}
regExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$regExpression.start, $regExpression.text] $a+ )
;
NL: 'n' | 'r';
And here are the errors after running the java -jar antlr-3.5.2-complete.jar Sample.g
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.CodeGenTreeWalker.getTokenElementST(CodeGenTreeWalker.java:311)
org.antlr.grammar.v3.CodeGenTreeWalker.notElement(CodeGenTreeWalker.java:2886)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2431)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2446)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.ebnf(CodeGenTreeWalker.java:3014)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2495)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.rule(CodeGenTreeWalker.java:1321)
org.antlr.grammar.v3.CodeGenTreeWalker.rules(CodeGenTreeWalker.java:955)
org.antlr.grammar.v3.CodeGenTreeWalker.grammarSpec(CodeGenTreeWalker.java:877)
org.antlr.grammar.v3.CodeGenTreeWalker.grammar_(CodeGenTreeWalker.java:518)
org.antlr.codegen.CodeGenerator.genRecognizer(CodeGenerator.java:415)
org.antlr.Tool.generateRecognizer(Tool.java:674)
org.antlr.Tool.process(Tool.java:487)
org.antlr.Tool.main(Tool.java:98)
antlr3
asked Jan 4 at 10:45
user10791468user10791468
11
add a comment |
0
I tried to use ANTLR3 to build a simple Regexpression parser, but it throws the internal error
Here is the Sample.g
grammar Sample;
options {
memoize=true;
output=AST;
}
tokens {
RegExp;
}
RegExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$RegExpression.start, $RegExpression.text] $a+ )
;
fragment NL: 'n' | 'r';
ANY : . ;
I run the command:
java -jar antlr-3.5.2-complete.jar -print Sample.g
and it gives this:
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.DefineGrammarItemsWalker.rewrite_atom(DefineGrammarItemsWalker.java:3896)
...
...
Updated according to comments
grammar Sample{
memoize=true;
output=AST;
}
tokens {
RegExp;
}
regExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$regExpression.start, $regExpression.text] $a+ )
;
NL: 'n' | 'r';
And here are the errors after running the java -jar antlr-3.5.2-complete.jar Sample.g
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.CodeGenTreeWalker.getTokenElementST(CodeGenTreeWalker.java:311)
org.antlr.grammar.v3.CodeGenTreeWalker.notElement(CodeGenTreeWalker.java:2886)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2431)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2446)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.ebnf(CodeGenTreeWalker.java:3014)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2495)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.rule(CodeGenTreeWalker.java:1321)
org.antlr.grammar.v3.CodeGenTreeWalker.rules(CodeGenTreeWalker.java:955)
org.antlr.grammar.v3.CodeGenTreeWalker.grammarSpec(CodeGenTreeWalker.java:877)
org.antlr.grammar.v3.CodeGenTreeWalker.grammar_(CodeGenTreeWalker.java:518)
org.antlr.codegen.CodeGenerator.genRecognizer(CodeGenerator.java:415)
org.antlr.Tool.generateRecognizer(Tool.java:674)
org.antlr.Tool.process(Tool.java:487)
org.antlr.Tool.main(Tool.java:98)
antlr3
asked Jan 4 at 10:45
user10791468user10791468
11
Why are you using such an old version of ANTLR? It's almost 5 years since 3.5.2 was last updated. I recommend you use ANTLR4 instead.
– Bart Kiers
Jan 4 at 11:01
It is a legacy code (being used) so it is not easy to move a big .g file to ANLTR 4
– user10791468
Jan 4 at 11:04
Someone else is also working on the same legacy code: stackoverflow.com/questions/54029954/… Homework, by any chance? Perhaps team up with that user? Not many people answering v3 questions anymore... Good luck anyway!
– Bart Kiers
Jan 4 at 11:32
@BartKiers v3 is far from dead yet, I see quite some projects around Hadoop still use it, e.g. Hive, Apache Pig.
– Jiri Tousek
Jan 7 at 9:03
Didn't say it was dead (at least, that isn't what I meant), I'm merely pointing out that many people answering questions here do so for v4. I for one used to answer quite a few v3 questions, but don't use v3 anymore and therefor don't have a quick test setup available on my machine.
– Bart Kiers
Jan 7 at 9:27
add a comment |
0
0
0
1
I tried to use ANTLR3 to build a simple Regexpression parser, but it throws the internal error
Here is the Sample.g
grammar Sample;
options {
memoize=true;
output=AST;
}
tokens {
RegExp;
}
RegExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$RegExpression.start, $RegExpression.text] $a+ )
;
fragment NL: 'n' | 'r';
ANY : . ;
I run the command:
java -jar antlr-3.5.2-complete.jar -print Sample.g
and it gives this:
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.DefineGrammarItemsWalker.rewrite_atom(DefineGrammarItemsWalker.java:3896)
...
...
Updated according to comments
grammar Sample{
memoize=true;
output=AST;
}
tokens {
RegExp;
}
regExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$regExpression.start, $regExpression.text] $a+ )
;
NL: 'n' | 'r';
And here are the errors after running the java -jar antlr-3.5.2-complete.jar Sample.g
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.CodeGenTreeWalker.getTokenElementST(CodeGenTreeWalker.java:311)
org.antlr.grammar.v3.CodeGenTreeWalker.notElement(CodeGenTreeWalker.java:2886)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2431)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2446)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.ebnf(CodeGenTreeWalker.java:3014)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2495)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.rule(CodeGenTreeWalker.java:1321)
org.antlr.grammar.v3.CodeGenTreeWalker.rules(CodeGenTreeWalker.java:955)
org.antlr.grammar.v3.CodeGenTreeWalker.grammarSpec(CodeGenTreeWalker.java:877)
org.antlr.grammar.v3.CodeGenTreeWalker.grammar_(CodeGenTreeWalker.java:518)
org.antlr.codegen.CodeGenerator.genRecognizer(CodeGenerator.java:415)
org.antlr.Tool.generateRecognizer(Tool.java:674)
org.antlr.Tool.process(Tool.java:487)
org.antlr.Tool.main(Tool.java:98)
antlr3
asked Jan 4 at 10:45
user10791468user10791468
11
I tried to use ANTLR3 to build a simple Regexpression parser, but it throws the internal error
Here is the Sample.g
grammar Sample;
options {
memoize=true;
output=AST;
}
tokens {
RegExp;
}
RegExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$RegExpression.start, $RegExpression.text] $a+ )
;
fragment NL: 'n' | 'r';
ANY : . ;
I run the command:
java -jar antlr-3.5.2-complete.jar -print Sample.g
and it gives this:
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.DefineGrammarItemsWalker.rewrite_atom(DefineGrammarItemsWalker.java:3896)
...
...
Updated according to comments
grammar Sample{
memoize=true;
output=AST;
}
tokens {
RegExp;
}
regExpression:
'/' (a=~('/' | NL))+ '/'
-> ^(RegExp[$regExpression.start, $regExpression.text] $a+ )
;
NL: 'n' | 'r';
And here are the errors after running the java -jar antlr-3.5.2-complete.jar Sample.g
error(10): internal error: Sample.g : java.lang.NullPointerException
org.antlr.grammar.v3.CodeGenTreeWalker.getTokenElementST(CodeGenTreeWalker.java:311)
org.antlr.grammar.v3.CodeGenTreeWalker.notElement(CodeGenTreeWalker.java:2886)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2431)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2446)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.ebnf(CodeGenTreeWalker.java:3014)
org.antlr.grammar.v3.CodeGenTreeWalker.element(CodeGenTreeWalker.java:2495)
org.antlr.grammar.v3.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:2250)
org.antlr.grammar.v3.CodeGenTreeWalker.block(CodeGenTreeWalker.java:1798)
org.antlr.grammar.v3.CodeGenTreeWalker.rule(CodeGenTreeWalker.java:1321)
org.antlr.grammar.v3.CodeGenTreeWalker.rules(CodeGenTreeWalker.java:955)
org.antlr.grammar.v3.CodeGenTreeWalker.grammarSpec(CodeGenTreeWalker.java:877)
org.antlr.grammar.v3.CodeGenTreeWalker.grammar_(CodeGenTreeWalker.java:518)
org.antlr.codegen.CodeGenerator.genRecognizer(CodeGenerator.java:415)
org.antlr.Tool.generateRecognizer(Tool.java:674)
org.antlr.Tool.process(Tool.java:487)
org.antlr.Tool.main(Tool.java:98)
antlr3
antlr3
asked Jan 4 at 10:45
user10791468user10791468
11
asked Jan 4 at 10:45
user10791468user10791468
11
edited Jan 8 at 10:36
user10791468
asked Jan 4 at 10:45
user10791468user10791468
11
asked Jan 4 at 10:45
user10791468user10791468
11
asked Jan 4 at 10:45
user10791468user10791468
11
11
Why are you using such an old version of ANTLR? It's almost 5 years since 3.5.2 was last updated. I recommend you use ANTLR4 instead.
– Bart Kiers
Jan 4 at 11:01
It is a legacy code (being used) so it is not easy to move a big .g file to ANLTR 4
– user10791468
Jan 4 at 11:04
Someone else is also working on the same legacy code: stackoverflow.com/questions/54029954/… Homework, by any chance? Perhaps team up with that user? Not many people answering v3 questions anymore... Good luck anyway!
– Bart Kiers
Jan 4 at 11:32
@BartKiers v3 is far from dead yet, I see quite some projects around Hadoop still use it, e.g. Hive, Apache Pig.
– Jiri Tousek
Jan 7 at 9:03
Didn't say it was dead (at least, that isn't what I meant), I'm merely pointing out that many people answering questions here do so for v4. I for one used to answer quite a few v3 questions, but don't use v3 anymore and therefor don't have a quick test setup available on my machine.
– Bart Kiers
Jan 7 at 9:27
add a comment |
Why are you using such an old version of ANTLR? It's almost 5 years since 3.5.2 was last updated. I recommend you use ANTLR4 instead.
– Bart Kiers
Jan 4 at 11:01
It is a legacy code (being used) so it is not easy to move a big .g file to ANLTR 4
– user10791468
Jan 4 at 11:04
Someone else is also working on the same legacy code: stackoverflow.com/questions/54029954/… Homework, by any chance? Perhaps team up with that user? Not many people answering v3 questions anymore... Good luck anyway!
– Bart Kiers
Jan 4 at 11:32
@BartKiers v3 is far from dead yet, I see quite some projects around Hadoop still use it, e.g. Hive, Apache Pig.
– Jiri Tousek
Jan 7 at 9:03
Didn't say it was dead (at least, that isn't what I meant), I'm merely pointing out that many people answering questions here do so for v4. I for one used to answer quite a few v3 questions, but don't use v3 anymore and therefor don't have a quick test setup available on my machine.
– Bart Kiers
Jan 7 at 9:27
Why are you using such an old version of ANTLR? It's almost 5 years since 3.5.2 was last updated. I recommend you use ANTLR4 instead.
– Bart Kiers
Jan 4 at 11:01
Why are you using such an old version of ANTLR? It's almost 5 years since 3.5.2 was last updated. I recommend you use ANTLR4 instead.
– Bart Kiers
Jan 4 at 11:01
It is a legacy code (being used) so it is not easy to move a big .g file to ANLTR 4
– user10791468
Jan 4 at 11:04
It is a legacy code (being used) so it is not easy to move a big .g file to ANLTR 4
– user10791468
Jan 4 at 11:04
Someone else is also working on the same legacy code: stackoverflow.com/questions/54029954/… Homework, by any chance? Perhaps team up with that user? Not many people answering v3 questions anymore... Good luck anyway!
– Bart Kiers
Jan 4 at 11:32
Someone else is also working on the same legacy code: stackoverflow.com/questions/54029954/… Homework, by any chance? Perhaps team up with that user? Not many people answering v3 questions anymore... Good luck anyway!
– Bart Kiers
Jan 4 at 11:32
@BartKiers v3 is far from dead yet, I see quite some projects around Hadoop still use it, e.g. Hive, Apache Pig.
– Jiri Tousek
Jan 7 at 9:03
@BartKiers v3 is far from dead yet, I see quite some projects around Hadoop still use it, e.g. Hive, Apache Pig.
– Jiri Tousek
Jan 7 at 9:03
Didn't say it was dead (at least, that isn't what I meant), I'm merely pointing out that many people answering questions here do so for v4. I for one used to answer quite a few v3 questions, but don't use v3 anymore and therefor don't have a quick test setup available on my machine.
– Bart Kiers
Jan 7 at 9:27
Didn't say it was dead (at least, that isn't what I meant), I'm merely pointing out that many people answering questions here do so for v4. I for one used to answer quite a few v3 questions, but don't use v3 anymore and therefor don't have a quick test setup available on my machine.
– Bart Kiers
Jan 7 at 9:27
add a comment |
1 Answer
1
active
oldest
votes
1
You're trying to use a rewrite rule (tree construction) on a lexer rule. That doesn't make sense.
In ANTLR, all rules with name starting with an uppercase letter are lexer rules. The tree construction is used on AST nodes, not on tokens themselves, so you have to use it on parser rules (starting with lowercase letter).
When you do that, keep in mind that your NL is a fragment now (you cannot use fragments in parser rules) and make sure your ANY token doesn't collide with anything else, i.e. define all needed tokens (/, NL etc.) and put them above the ANY token definition.
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
Haha, the tree rewrite rule was something even I without a test setup could have answered/spotted! Good call.
– Bart Kiers
Jan 7 at 9:28
I have updated the code, but it seems still producing the NullPointerException.
– user10791468
Jan 8 at 10:37
I can't see howa=~('/' | NL)could ever match anything, provided thatNLand/are the only tokens defined in your grammar as posted.
– Jiri Tousek
Jan 8 at 12:01
Could you give me more hints? Basically I am trying to match a regular expression in lexer and would like to transform it to AST
– user10791468
Jan 14 at 10:48
add a comment |
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1 Answer
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You're trying to use a rewrite rule (tree construction) on a lexer rule. That doesn't make sense.
In ANTLR, all rules with name starting with an uppercase letter are lexer rules. The tree construction is used on AST nodes, not on tokens themselves, so you have to use it on parser rules (starting with lowercase letter).
When you do that, keep in mind that your NL is a fragment now (you cannot use fragments in parser rules) and make sure your ANY token doesn't collide with anything else, i.e. define all needed tokens (/, NL etc.) and put them above the ANY token definition.
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
Haha, the tree rewrite rule was something even I without a test setup could have answered/spotted! Good call.
– Bart Kiers
Jan 7 at 9:28
I have updated the code, but it seems still producing the NullPointerException.
– user10791468
Jan 8 at 10:37
I can't see howa=~('/' | NL)could ever match anything, provided thatNLand/are the only tokens defined in your grammar as posted.
– Jiri Tousek
Jan 8 at 12:01
Could you give me more hints? Basically I am trying to match a regular expression in lexer and would like to transform it to AST
– user10791468
Jan 14 at 10:48
add a comment |
1
You're trying to use a rewrite rule (tree construction) on a lexer rule. That doesn't make sense.
In ANTLR, all rules with name starting with an uppercase letter are lexer rules. The tree construction is used on AST nodes, not on tokens themselves, so you have to use it on parser rules (starting with lowercase letter).
When you do that, keep in mind that your NL is a fragment now (you cannot use fragments in parser rules) and make sure your ANY token doesn't collide with anything else, i.e. define all needed tokens (/, NL etc.) and put them above the ANY token definition.
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
Haha, the tree rewrite rule was something even I without a test setup could have answered/spotted! Good call.
– Bart Kiers
Jan 7 at 9:28
I have updated the code, but it seems still producing the NullPointerException.
– user10791468
Jan 8 at 10:37
I can't see howa=~('/' | NL)could ever match anything, provided thatNLand/are the only tokens defined in your grammar as posted.
– Jiri Tousek
Jan 8 at 12:01
Could you give me more hints? Basically I am trying to match a regular expression in lexer and would like to transform it to AST
– user10791468
Jan 14 at 10:48
add a comment |
1
1
1
You're trying to use a rewrite rule (tree construction) on a lexer rule. That doesn't make sense.
In ANTLR, all rules with name starting with an uppercase letter are lexer rules. The tree construction is used on AST nodes, not on tokens themselves, so you have to use it on parser rules (starting with lowercase letter).
When you do that, keep in mind that your NL is a fragment now (you cannot use fragments in parser rules) and make sure your ANY token doesn't collide with anything else, i.e. define all needed tokens (/, NL etc.) and put them above the ANY token definition.
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
You're trying to use a rewrite rule (tree construction) on a lexer rule. That doesn't make sense.
In ANTLR, all rules with name starting with an uppercase letter are lexer rules. The tree construction is used on AST nodes, not on tokens themselves, so you have to use it on parser rules (starting with lowercase letter).
When you do that, keep in mind that your NL is a fragment now (you cannot use fragments in parser rules) and make sure your ANY token doesn't collide with anything else, i.e. define all needed tokens (/, NL etc.) and put them above the ANY token definition.
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
answered Jan 7 at 8:59
Jiri TousekJiri Tousek
10.5k52240
10.5k52240
Haha, the tree rewrite rule was something even I without a test setup could have answered/spotted! Good call.
– Bart Kiers
Jan 7 at 9:28
I have updated the code, but it seems still producing the NullPointerException.
– user10791468
Jan 8 at 10:37
I can't see howa=~('/' | NL)could ever match anything, provided thatNLand/are the only tokens defined in your grammar as posted.
– Jiri Tousek
Jan 8 at 12:01
Could you give me more hints? Basically I am trying to match a regular expression in lexer and would like to transform it to AST
– user10791468
Jan 14 at 10:48
add a comment |
Haha, the tree rewrite rule was something even I without a test setup could have answered/spotted! Good call.
– Bart Kiers
Jan 7 at 9:28
I have updated the code, but it seems still producing the NullPointerException.
– user10791468
Jan 8 at 10:37
I can't see howa=~('/' | NL)could ever match anything, provided thatNLand/are the only tokens defined in your grammar as posted.
– Jiri Tousek
Jan 8 at 12:01
Could you give me more hints? Basically I am trying to match a regular expression in lexer and would like to transform it to AST
– user10791468
Jan 14 at 10:48
Haha, the tree rewrite rule was something even I without a test setup could have answered/spotted! Good call.
– Bart Kiers
Jan 7 at 9:28
Haha, the tree rewrite rule was something even I without a test setup could have answered/spotted! Good call.
– Bart Kiers
Jan 7 at 9:28
I have updated the code, but it seems still producing the NullPointerException.
– user10791468
Jan 8 at 10:37
I have updated the code, but it seems still producing the NullPointerException.
– user10791468
Jan 8 at 10:37
I can't see how
a=~('/' | NL) could ever match anything, provided that NL and / are the only tokens defined in your grammar as posted.– Jiri Tousek
Jan 8 at 12:01
I can't see how
a=~('/' | NL) could ever match anything, provided that NL and / are the only tokens defined in your grammar as posted.– Jiri Tousek
Jan 8 at 12:01
Could you give me more hints? Basically I am trying to match a regular expression in lexer and would like to transform it to AST
– user10791468
Jan 14 at 10:48
Could you give me more hints? Basically I am trying to match a regular expression in lexer and would like to transform it to AST
– user10791468
Jan 14 at 10:48
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Why are you using such an old version of ANTLR? It's almost 5 years since 3.5.2 was last updated. I recommend you use ANTLR4 instead.
– Bart Kiers
Jan 4 at 11:01
It is a legacy code (being used) so it is not easy to move a big .g file to ANLTR 4
– user10791468
Jan 4 at 11:04
Someone else is also working on the same legacy code: stackoverflow.com/questions/54029954/… Homework, by any chance? Perhaps team up with that user? Not many people answering v3 questions anymore... Good luck anyway!
– Bart Kiers
Jan 4 at 11:32
@BartKiers v3 is far from dead yet, I see quite some projects around Hadoop still use it, e.g. Hive, Apache Pig.
– Jiri Tousek
Jan 7 at 9:03
Didn't say it was dead (at least, that isn't what I meant), I'm merely pointing out that many people answering questions here do so for v4. I for one used to answer quite a few v3 questions, but don't use v3 anymore and therefor don't have a quick test setup available on my machine.
– Bart Kiers
Jan 7 at 9:27