[stringtemplate-interest] [ST4 Beta4] Inconsistent handling of starting/trailing newline in embedded region

[Udo Borkowski]

Hi,

I suggest to discard a trailing and leading newline in an embedded region. Also the newline following an <@end> should not be discarded.

This is consistent with the way these newlines are handled for templates and externally defined regions (trimOneStarting/TrailingNewline).

Currently a starting/trailing newline in an embedded region is handled differently than ones in an external region definition. This leads to problems e.g. when an embedded region is later redefined (by an external region in a sub group).

E.g.

This template using embedded regions:

==========
embedded() ::= <<
---------
	a<@e1>e1<@end>b
---------
	a<@e2>
	e2
	<@end>b
---------
	a
	<@e3>
	e3
	<@end>b
---------
	a
	<@e4>
	e4
	<@end>
	b
---------
>>
==========

generates this output:

==========
---------
	ae1b
---------
	ae2
b
---------
	a
	e3
b
---------
	a
	e4
	b
---------
==========

If one defines the same template using external regions, e.g.:

==========
nonEmbedded() ::= <<
---------
	a<@r1()>b
---------
	a<@r2()>b
---------
	a
	<@r3()>b
---------
	a
	<@r4()>
	b
---------
>>

@nonEmbedded.r1() ::= <<r1>>

@nonEmbedded.r2() ::= <<
r2
>>

@nonEmbedded.r3() ::= <<
r3
>>

@nonEmbedded.r4() ::= <<
r4
>>
==========

the result is different (and more what I would have expected):
==========
---------
	ar1b
---------
	ar2b
---------
	a
	r3b
---------
	a
	r4
	b
---------
==========

Back to the embedded case: 
when I now redefined the embedded regions in a different group with the same stuff as for the "nonEmbedded" case, with this
==========
@embedded.e1() ::= <<r1>>

@embedded.e2() ::= <<
r2
>>

@embedded.e3() ::= <<
r3
>>

@embedded.e4() ::= <<
r4
>>
==========

I got a completely different picture:

==========
---------
	ar1b
---------
	ar2b
---------
	a
r3b
---------
	a
r4b
---------
==========


Udo

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