cobol - COBOL 中是否允许嵌套的抄写本？

Question

我知道许多 COBOL 编译器确实允许嵌套副本(具有不同的深度)，但我没有找到任何“官方”规则。问题:

1. 是否有明确允许或禁止嵌套副本的 COBOL 标准？

2. 有没有不允许嵌套copybooks的COBOL编译器？

Answer 1

标准允许嵌套的副本，但不允许在 REPLACING 子句中提及或操纵任何 COPY 语句。从标准的 COPY 语句，一般规则 11 到 14(COBOL 2014 7.2.2.3，在 COBOL 2002 7.1.2.3 中相同):

11. If the REPLACING phrase is specified, the library text shall not contain a COPY statement.
12. ...
13. If the REPLACING phrase is not specified, the library text may contain a COPY statement that does not include a REPLACING phrase. The implementation shall support nesting of at least 5 levels, including the first COPY statement in the sequence. The library text being copied shall not cause the processing of a COPY statement that directly or indirectly copies itself.
14. The replacing action of a COPY statement shall not introduce a COPY statement, a SOURCE FORMAT directive, a comment or a blank line.