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https://issues.apache.org/jira/browse/GROOVY-9612?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17149158#comment-17149158
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Paul King edited comment on GROOVY-9612 at 7/1/20, 6:38 AM:
------------------------------------------------------------
I would phrase things differently to what Daniel said. Groovy has never (at
least not since 1.0) supported the syntax:
{code:java}
println
(
100
)
{code}
as a single statement. This ties back to semicolon being a statement separator
in Groovy (not statement terminator like in Java).
The general rule of parsing is that end of line terminates the statement
except when it wouldn't validly end a statement.
So, this is fine:
{code:java}
println (
100
)
{code}
But {{println}} on its own could be a property. You can work around this
limitation in various ways, e.g. using a trailing backslash:
{code:java}
println \
(
100
)
{code}
We do make exceptions to the general rule, e.g. we do lookahead in various
situations including closures, e.g. the above limitations don't exist and
workarounds not needed for:
{code:java}
def println(Closure c) { println c.call() }
println
{
100
}
{code}
When designing Groovy 3, we looked at whether we could also do lookahead for
brackets. Adding such support would be a breaking change. This is different to
the closure case since lookahead for closures has been around for a long time.
As an example, this code:
{code:java}
binding.variables.println = 42
println
(
100
)
{code}
prints nothing and returns 100 in all previous Groovy versions. If we supported
the lookahead for brackets, it would print 100 and return null. We haven't, so
far, been convinced that such a breaking change and added complexity to the
parser would be justified for marginal extra Java compatibility. It isn't a
goal of Groovy to be 100% Java compatible for all styles, we just try to be
very close whenever we can.
was (Author: paulk):
I would phrase things differently to what Daniel said. Groovy has never (at
least not since 1.0) supported the syntax:
{code:java}
println
(
100
)
{code}
as a single statement. This ties back to semicolon being a statement separator
in Groovy (not statement terminator like in Java).
The general rule of parsing is that end of line terminates the statement
except when it wouldn't validly end a statement.
So, this is fine:
{code:java}
println (
100
)
{code}
But {{println}} on its own could be a property. You can work around this
limitation in various ways, e.g. using a trailing backslash:
{code:java}
println \
(
100
)
{code}
We do make exceptions to the general rule, e.g. we do lookahead in various
situations including closures, e.g. the above limitations don't exist and
workarounds not needed for:
{code:java}
def println(Closure c) { println c.call() }
println
{
100
}
{code}
When designing Groovy 3, we looked at whether we could also do lookahead for
brackets. Adding such support would be a breaking change. This is different to
the closure case since lookahead for closures has been around for a long time.
As an example, this code:
{code:java}
binding.variables.println = 42
println
(
100
)
{code}
prints nothing and returns 100 in all previous Groovy versions. If we supported
the lookahead for brackets, it would print 100 and return null. We haven't been
convinced that such a breaking change and added complexity to the parser would
be justified for marginal extra Java compatibility. It isn't a goal of Groovy
to be 100% Java compatible for all styles, we just try to be very close
whenever we can.
> Should parse parenthesis and bracket after newline correctly
> ------------------------------------------------------------
>
> Key: GROOVY-9612
> URL: https://issues.apache.org/jira/browse/GROOVY-9612
> Project: Groovy
> Issue Type: Wish
> Components: parser
> Affects Versions: 3.0.4
> Reporter: Laurent RICHARD de LAPRADE
> Priority: Major
>
> For example, this should compile correctly. Current groovy parser forces
> coding style format which is not the one we choose when we code Java.
> {code:java}
> import java.io.*;
> import groovy.io.*;
> def dir = new File("C:\\");
> dir.eachFileRecurse
> (
> f
> ->
> println(f.name)
> );
> {code}
> groovy.lang.MissingPropertyException: No such property: eachFileRecurse for
> class: java.io.File
>
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