Unknown syntax in IBM research paper

Question

I'm reading a research paper High Performance Dynamic Lock-Free Hash Tables and List-Based Sets (Maged M. Michael) and I don't understand this pseudo-code syntax that's being used for examples.

Specifically these parts:

〈pmark,cur,ptag〉: MarkPtrType;
〈cmark,next,ctag〉: MarkPtrType;

nodeˆ.〈Mark,Next〉←〈0,cur〉;
if CAS(prev,〈0,cur,ptag〉,〈0,node,ptag+1〉)

Eg. (page 5, chapter 3)

UPDATE:

The ˆ. seems to be a Pascal notation for dereferencing the pointer and accessing the variable in the record (https://stackoverflow.com/a/1814936/8524584).
The ← arrow seems to be a Haskell like do notation operator for assignment, that assigns the result of an operation to a variable. This is a bit strange, since the paper is nearly a decade older than Haskell. It's probably some notation that Haskell also borrowed from. (https://en.wikibooks.org/wiki/Haskell/do_notation#Translating_the_bind_operator)
The 〈a, b〉 is a mathematical vector notation for an inner product of a vector (https://mathworld.wolfram.com/InnerProduct.html)

user_8524584 · Answer

The wide angle bracket notation seems to be either an ad-hoc list notation or manipulation of multiple variables on a single line (thanks @graybeard for pointing it out). It might even be some kind of tuple.

This is what 〈pmark,cur,ptag〉: MarkPtrType; would look like in a C like language:

MarkPtrType pmark;
MarkPtrType cur;
MarkPtrType ptag;

// or some list assignment notation
// or a tuple

The ˆ. seems to be a Pascal notation for dereferencing the pointer and accessing the variable in the record (https://stackoverflow.com/a/1814936/8524584).

The ← arrow is an APL assignment notation, also similar to the Haskell's do notation operator for assignment.

Unknown syntax in IBM research paper

1 Answers