[alfiedotwtf]

> Most popular programming languages have the defect that they impose a sequential semantics even where it is not needed. There have been programming languages without this defect, e.g. Occam, but they have not become widespread.

We have memory ordering functions to let compilers know the atomic operation preference of the programmer… couldn’t we do the same for maths and in general a set of expressions?

[adrian_b]

An example of programming language syntax that avoids to specify sequential execution where not needed is to specify that a sequence of expressions separated by semicolons must be executed sequentially, but a sequence of expressions separated by commas may be executed in any order or concurrently.

This is just a minor change from the syntax of the most popular programming languages, because they typically already specify that the order of evaluation of the expressions used for the arguments of a function, which are separated by commas, can be arbitrary.

Early in its history, the C language has been close to specifying this behavior for its comma operator, but unfortunately its designers have changed their mind and they have made the comma operator behave like a semicolon, in order to be able to use it inside for statement headers, where the semicolons have a different meaning. A much better solution for C, instead of making both comma and semicolon to have the same behavior, would have been to allow a block to appear in any place where an expression is expected, giving it the value of the last expression evaluated in the block.