Is this the programming language that works without a lexer/parser and a grammar? Why aren't there more programming languages written this way? Seems easier to implement.
The parser's behavior is not specified except in the implementation, which is messy C. I was once loosely involved in a project that tried to reimplement it, which turns out to be extremely difficult, and was laughed at by Brent Welch. Indeed, it failed on countless edge cases. lex and yacc (or whatever) at least isolate this part of the language, making it much easier to have more than one implementation.
Tcl's C implementation is far from messy. Its actually one of the best commented C based language code bases i have ever seen. But your project was doomed by false assumptions. (oh, and Tcl has more than one implementation, e.g. there is a version based on Parrot for example, http://code.google.com/p/partcl/ or the JACL interpreter based on the JVM).