Mikroelektronika MIKROE-738 Datenbogen

256

mikoC PRO for PIC32

MikroElektronika

The  compound  statement,  or  block,  is  a  list  (possibly  empty)  of  statements  enclosed  in  matching  braces 

{  }

. 

Syntactically, the block can be considered to be a single statement, but it also plays a role in the scoping of identifiers. 

An identifier declared within the block has a scope starting at the point of declaration and ending at the closing brace. 

Blocks can be nested to any depth up to the limits of memory.

For example, the 

for

 loop expects one statement in its body, so we can pass it a compound statement:

for (i = 0; i < n; i++ ) {

  int temp = a[i];

  a[i] = b[i];

  b[i] = temp;

}

Note that, unlike other statements, compound statements do not end with semicolon (

;

), i.e. there is never a semicolon 

following the closing brace.

Preprocessor is an integrated text processor which prepares the source code for compiling. Preprocessor allows:

 

- inserting text from a specifed file to a certain point in the code (see File Inclusion), 

 

- replacing specific lexical symbols with other symbols (see Macros), 

 

- conditional compiling which conditionally includes or omits parts of the code (see Conditional Compilation). 

Note that preprocessor analyzes text at token level, not at individual character level. Preprocessor is controled by 

means of preprocessor directives and preprocessor operators.

Any line in the source code with a leading 

# 

is taken as a preprocessing directive (or control line), unless 

#

 is within 

a string literal, in a character constant, or embedded in a comment. The initial

  #

 can be preceded or followed by a 

whitespace (excluding new lines).

A null directive consists of a line containing the single character 

#

. This line is always ignored.

Preprocessor directives are usually placed at the beginning of the source code, but they can legally appear at any 

point in a program. The mikroC PRO for PIC32 preprocessor detects preprocessor directives and parses the tokens 

embedded in them. A directive is in effect from its declaration to the end of the program file.

Here is one commonly used directive:

#include <math.h>