Source input considerations

Extended continuation-indicators can be used in any source statement, including macro statements and statements included by the COPY instruction. This feature is intended for source lines containing double-byte data, however it becomes available to all lines when the DBCS option is set.
On a line with a non-space continuation-indicator, the end column is the first column to the left of the continuation-indicator which has a value different from the continuation-indicator.
When converting existing programs for assembly with the DBCS option, ensure that continuation-indicators are different from the adjacent data in the end column.
The extended continuation-indicators must not be extended into the continue column, otherwise the extended continuation-indicators are treated as data, and the assembler issues the following error message:
```
ASMA205E Extended continuation column must not extend into continue
column
```
For SI and SO to be removed at continuation points, the SI must be in the end column, and the SO must be in the continue column of the next line.