Self Made C Scripting Language.

[patrink]

Hey everyone, I have a few questions regarding creating my own scripting language.

I'm having a bit of trouble when it comes to tokenizing the file (ie, the lexical analyzer). My first version, ashamed as I am to say it, was basically just a huge else-if statement using strcmp(). Eventually I ended up using strtok() which was fine for code such as:

var SomeVariable; /* this assigns a variable named SomeVariable */
SomeVariable = 3; /* assigns 3 to SomeVariable */

but I ran into a problem. How would I tokenize and process something such as:

SomeVariable = (3 + 4) - 2 * 3; /* this should make SomeVariable = 1 */

because strtok() doesn't return what it finds, it only returns a string which contains the next token, so I have some troubles when doing calculations because if I set it up to tokenize brackets, I don't know if it found a bracket or not, It would just return a string.

I'm just wondering if anyone could give me some tips/pseudocode on how to overcome this.

[kmess]

The expression you're referring to is in what's called "infix" notation, and you will need to convert it to "postfix" notation to evaluate it properly.

Check out InFix to PostFix and PostFix expression evaluation.