Form compiler checking invalid layout definition

It is better to identify form layout mistakes when the form is compiled, rather than at runtime.

Starting with version 2.20.05, the fglform compiler performs more layout checking than before. Thus, existing (invalid) forms that compiled with prior versions of Genero may no longer compile with 2.20.05. This strict checking is done to detect layout mistakes during form design, instead of having the front-ends render invalid forms in a unknown manner at run time.

For example, the following form definitions are invalid and will raise a compilation error with fglform:

SCHEMA FORMONLY
LAYOUT
GRID
{
  [f01:  |f02    ]     -- HBox layout tags in lists are denied 
  [f01:  |f02    ]
  [f01:  |f02    ]
  [f01:  |f02    ]
}
END
END

SCHEMA FORMONLY
LAYOUT
GRID
{
  [f01    ]  [f02    ]
  [f01    ]       [f02    ]   -- Misaligned field tags (vertical)
  [f01    ]  [f02    ]
  [f01    ]       [f02    ]
}
END
END

SCHEMA FORMONLY
LAYOUT
GRID
{
  [f01][f01][f01]  [f01]   -- Misaligned field tags (horizontal)
}
END
END