4.12 Macro Calls

4.12 Macro Calls

A macro call consists of a name optionally followed by an

actual parameter list. The number of parameters in the actual

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parameter list must be the same as the number of formal

parameters specified in the definition of the macro. If the macro

Developer

has no formal parameter list, its call must have no actual

parameter list.

Reference

1 Introduction

macro_call = name [actual_parameter_list]

2 Interface

actual_parameter_list =

      "@(" actpar { "@," actpar } "@)"

3 Scanner

actpar     = expression |

4 Parser

             ( whitespace "@""" expression

5 Analyser

               "@""" whitespace )

6 Tangle

whitespace = {" " | eol }

7 Weave

FunnelWeb allows parameters to be passed directly, or

8 Shell

delimited by special double quotes. Each form is useful under

9 Commands

different circumstances. Direct specification is useful where the

10 Glossary

parameters are short and can be all placed on one line. Double

11 References

quoted parameters allow whitespace on either side (that is not

considered part of the parameter) and are useful for laying out

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rather messy parameters. Here are examples of the two forms.

@@(

   @"x:=1;@"  @,

   @"x<=10;@" @,

   @"print "x=%u, x^2=%u",x,x*x;

   x:=x+1;@+@"

@)

@@(red@,green@,blue@,yellow@)

The two forms may be mixed within the same parameter list.

Experience has shown that, in most FunnelWeb files, the vast

majority of macros have no parameters.

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Copyright   Ross N. Williams 1992,1999. All rights

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