Re:Ada for the C++ and Java Developer [pdf]
by stephen_g on Sunday March 28, 2021 @10:35AM
(#26610715)
Wow, reading through some of these examples, it’s pretty clear where VHDL got it’s syntax! I think I do recall some relation between it and Ada, but it’s almost uncannily close. (Looking up now, it was apparently a requirement for it to be based as much as possible on Ada).
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VHDL was initially developed by the DoD back in the time when there was a strong push towards unification of programming languages used in government/defense contracts.
Newer VHDL deviates from Ada syntax in some unfortunate ways that can lead to confusion. For example ".all", in Ada is used to "dereference pointers" while in VHDL it is used to import everything from a library.
Also, coming from Ada you eventually realize that many FPGA vendor's tools are non-conforming to the standard in regards to certain features that are seldomly used by hardware designers but are bread and butter for Ada developers. (enum -> int, int -> enum conversions were partly unsupported in the Xilinx toolchains some years ago, not sure if the problem persists.)
Re:Ada for the C++ and Java Developer [pdf]
by bXVsbGVy on Sunday March 28, 2021 @12:16PM
(#26611532)
> For example ".all", in Ada is used to "dereference pointers" while in VHDL it is used to import everything from a library.
In VHDL, the meaning of the suffix all depends on kind of the prefix. When the prefix is an object of access type, it behaves similarly to Ada.