Blech version 0.6.0

We are happy to announce a new release of the Blech compiler and language services for VS Code.

Language features are:

• The syntax of the statement <code>run</code> has changed. It now allows local variable declarations. A <code>return</code> statement may now have an activity call as an argument:

  • run foo = Act()

    used to be foo = run Act()

  • run var foo = Act()

    Here foo is declared in-place and can be used after the run statement.

  • return run Act()

    Here the value returned by Act is directly returned further up.

• It is now possible to reorder function parameters when linking to external C functions. This is useful to map Blech’s input and output parameters to the single parameter list of a C function:

    @[CFunction(binding = "myCfunction($2, $1)")]
    extern function doStuff(a: nat8)(b: nat8)
  

• Some annotations may contain string literals. We now support single and (indented) multi line string literals. This is useful if you want to define the right-hand side of a macro as your C-binding:

    @[CFunction (binding = """
                           do {
                             *$2 = $1;
                             *$2 = *$2 + 1;
                           } while (0)
                           """)]
    extern function doStuff(a: nat8)(b: nat8)
  

  Note that you have to follow the Blech-C-interface when accessing Blech parameters from C. $1 is input parameter a: nat8 which is passed by value because it has a simple type. $2 is output parameter b: nat8 which is passed by reference as a pointer.

On the technical side we have fixed a few bugs and issues and improved code generation. The latter now uses “activity contexts” to store activity local data and program counters instead of passing around individual values. This is a preparation for the upcoming module system.

• ←Previous
Next→