Mikroelektronika MIKROE-738 Datenbogen

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mikoC PRO for PIC32

MikroElektronika

Token is the smallest element of a C program that compiler can recognize. The parser separates tokens from the input 

stream by creating the longest token possible using the input characters in a left–to–right scan.

The mikroC PRO for PIC32 recognizes the following kinds of tokens:

- keywords 

- identifiers 

- constants 

- operators 

- punctuators (also known as separators) 

Tokens can be concatenated (pasted) by means of the preprocessor operator 

##

. See the Preprocessor Operators for 

details.

Token Extraction Example

Here is an example of token extraction. Take a look at the following example code sequence:

inter =  a+++b;

First, note that 

inter

 would be parsed as a single identifier, rather than as the keyword 

int 

followed by the identifier 

er

.

The programmer who has written the code might have intended to write 

inter = a + (++b)

, but it wouldn’t work 

that way. The compiler would parse it into the seven following tokens:

inter    // variable identifier

=        // assignment operator

a        // variable identifier

++       // postincrement operator

+        // addition operator

b        // variable identifier

;        // statement terminator

Note that 

+++

 parses as 

++

 (the longest token possible) followed by 

+

.

According to the operator precedence rules, our code sequence is actually:

inter (a++)+b;