FuncCall

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FuncCall   ::= Primary Actuals
Actuals    ::= ( Expr*, )

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The function call mechanism provides special treatment for the identifier consisting of a single period, called the current environment and pronounced dot. Dot is typically assigned a binding that contains the tools, switches, and file system required for the rest of the build. The initial environment, C-initial (see Section A.3.3 above), does not bind dot (that is, ``_defined(C-initial, ".") == false'').

When a function is called, the context in which its body executes may bind ``.'' to a value established as follows:

• if the function is defined with $n$ formals and called with $n$ or fewer actuals, then the value for ``.'' at the point of call is bound to the implicit formal parameter named ``.'' in the callee;

• if the function is defined with $n$ formals and called with $n+1$ actuals, then the value bound to the implicit formal parameter named ``.'' is the value of the last actual.

Thus, the binding for ``.'', if any, is passed through the dynamic call chain until it is altered either explicitly by an Assign statement (Section A.3.3.9) or implicitly by calling a function with an extra actual parameter. The pseudo-code shown in Table A.8 makes this precise. In this code, the comparison with $\langle\mbox{emptyExpr}\rangle$ has not been formalized, but it should be intuitively clear.

Table A.8: Evaluation rule for FuncCall.