Fixed Insertions¶

Felix also allows you to insert executable code literally in fixed places inside Felix code. There are two cases.

Lifting Plain Statements¶

Statements can be lifted with the plain cstmt statement:

proc hello() {
  cstmt """
    std::cout<< "Hello World" << ::std::endl;
    std::cout<< "C++ Embedded in Felix" << ::std::endl;
  """;
}

If the C statement does not return, use the noreturn option:

proc leave() {
  noreturn cstmt "::std::exit(0);";
}

Lifted code can accept arguments:

proc error(x:int) {
  noreturn cstmt "::std::exit($1);" x;
}

The argument can be a tuple, the components are inserted by the usual rules for C bindings using $9 style notation.

An expression can be lifted too, however the type must be given:

var x = cexpr[int]"42" endcexpr;

If the expression is not atomic, it is wise to enclose it in parentheses.

There is a short hand for lifting variables:

cvar[int] M_PI;

which is equivalent to:

cexpr[int]"M_PI" endcexpr;