The lastest z390 PTF v1.4.02e has a new open source translator to support structured programming extensions for mainframe conditional macro assembler coding. The extensions include:
1. AIF, AELSEIF, AELSE, AEND - for alternate selection of macro code blocks
2. AWHILE, AUNTIL, AEXIT, AEND - for repetition of macro code blocks
3. ASELECT, AWHEN, AELSE, AEXIT, AEND for selection of macro code block based on index
4. APM, AENTRY, AEXIT, AEND - for performing labeled macro code block.
The source for the translator including both bootstrap version and structured version can be found along with test programs on this web page:
The next full release of z390 v1.4.03 will have these extensions built into the macro processor so translation as a separate step is not required.