Explicit `Rec.` prefix on unsupported runtime not caught at compile time, may freeze client

[dzzzb]

Describe the bug If a page has added explicit Rec. qualifiers to fields or properties, these are not supported in runtimes before 6, but there are no warnings at compile-time, so if we backport an extension or just include Rec. out of habit to an older runtime, we find only later that it doesn't work, and have to waste our time and disturb users by republishing without Rec.

Worse, not all unsupported cases are even reported at runtime, at least not until you go looking elsewhere... for example, I just found that Rec. in a HideValue expression just causes the client to lock up and spew a bunch of errors in an infinite loop!

To Reproduce Here is the page after I mostly fixed it but forgot the Rec. in the HideValue expression, which caused the inability to open the page as it silently spun an infinite loop as per above.

Expected behavior If compiling against a runtime that doesn't support Rec. anywhere, stop the developer with an error, rather than deferring that until runtime and wasting everyone's time. Please?

5. Versions:

• AL Language: 6.1.397164
• Business Central: Version: GB Business Central 15.5 (Platform 15.0.41893.0 + Application 15.5.41926.0)

[atoader]

@dtkb is this still a problem?

[dzzzb]

Yes, the compiler still doesn't warn that unsupported Rec. prefixes will either cause a runtime error or simply crash the client. Same example, redone:

I would expect that

• (a CU for such older releases - in this case Version: Platform 15.0.36510.0 + Application 15.0.36649.0 - will stop such code causing crashes and just give a 'proper' runtime error. maybe it already does; I am running an old version on purpose to match a user site.)
• the AL compiler would know which combinations of versions and properties do and don't support Rec. prefixes and, if unsupported, make that a compile-time error or at least a warning, so we don't waste time publishing that code to site only to have the client crash.

Name: AL Language
Id: ms-dynamics-smb.al
Description: AL development tools for Dynamics 365 Business Central
Version: 7.1.453917
Publisher: Microsoft
VS Marketplace Link: https://marketplace.visualstudio.com/items?itemName=ms-dynamics-smb.al