Date: Fri Aug 11 2006 - 03:10:58 PDT
Thanks. OK, that brings me to several comments: 1. I think that 4.16 should be a sub-section of 4.14. 2. I think that the reference to 4.15 for describing casting to an enum type should be to 4.10.4 instead. 3. The description of $cast as a type of assignment seems to fail when we talk about enums, since you can't assign an integral value to an enum. 4. Once upon a time, one could read the Verilog LRM and understand it without knowing some C first. This started changing in Verilog-2001 and now in SystemVerilog, you really cannot understand the LRM without knowing some C. I find that unfortunate. I noticed this when I found that "casting" is not defined. 5. More important, the term "static cast" is not defined. This makes the sentence, "In a static cast, the expression to be cast shall be enclosed in parentheses that are prefixed with the casting type and an apostrophe," somewhat cryptic. 6. The end of that paragraph says, "if the casting type is a bit-stream type, the behavior shall be as described in 4.16." However, the term "bit-stream type" is itself not defined at this point in the LRM. It is defined only in 4.16. Nor is the term "bit-stream cast" itself ever defined. 7. Can every static cast be described as a bit-stream cast also? 8. It would be nice if the glossary appeared at the beginning of the LRM instead of at the end, but it would change the clause numbering, and I am not sure the IEEE would allow it. Shalom ________________________________ From: owner-sv-bc@server.eda-stds.org [mailto:owner-sv-bc@server.eda-stds.org] On Behalf Of Brad Pierce Sent: Thursday, August 10, 2006 6:16 PM To: sv-bc@server.eda-stds.org Subject: Re: [sv-bc] types of casting Bit-stream casting is just a kind of static casting. It is tried when the casting expression is not assignment-compatible with the casting type. "In a static cast, the expression to be cast shall be enclosed in parentheses that are prefixed with the casting type and an apostrophe. If the expression is assignment compatible with the casting type, then the cast shall return the value that a variable of the casting type would hold after being assigned the expression. If the expression is not assignment compatible with the casting type, then if the casting type is an enumerated type, the behavior shall be as described as in 4.15, and if the casting type is a bit-stream type, the behavior shall be as described in 4.16." -- Brad ________________________________ From: owner-sv-bc@eda-stds.org [mailto:owner-sv-bc@eda-stds.org] On Behalf Of Bresticker, Shalom Sent: Thursday, August 10, 2006 1:59 AM To: sv-bc@eda-stds.org Subject: [sv-bc] types of casting Hi, What are the essential differences between static casting as described in 4.14 and bit-stream casting as described in 4.16 ? The differences don't seem to be clearly described. Thanks, Shalom Shalom Bresticker Intel Jerusalem LAD DA +972 2 589-6852 +972 54 721-1033 I don't represent Intel
