https://github.com/wernsey/Fiz

A small but functional interpreter for a Tcl-like language
https://github.com/wernsey/Fiz

Last synced: about 2 months ago
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A small but functional interpreter for a Tcl-like language

• Host: GitHub
• URL: https://github.com/wernsey/Fiz
• Owner: wernsey
• License: unlicense
• Created: 2015-02-23T08:31:36.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2019-11-15T09:26:23.000Z (over 4 years ago)
• Last Synced: 2024-01-29T06:12:44.280Z (5 months ago)
• Language: C
• Size: 84 KB
• Stars: 8
• Watchers: 5
• Forks: 2
• Open Issues: 2
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Lists

• AwesomeInterpreter - Fiz

README

        
# Fiz - A Tcl-like scripting language.

I was inspired to write a Tcl interpreter after I realised how simple

the language really was (it took me some time to become enlightened)

and how elegant the API for embedding it in another program could be.

I call it a _Tcl-like_ language because it doesn't attempt to implement all the

features of Tcl. It has several useful features though, like `dict` and `expr`

and so forth.

Due to limits in the expression evaluator you can't just write an

`if`- or `while`-statement condition like

    if {$x<2} {puts "Yea"};

because the `{$x<2}` will be treated as a command. You should rather use 

the `expr` command, as follows:

    if {expr $x<2} {puts "Yea"};

This interpreter goes for simplicity. It uses strings to represents all

variables, with the result that it has to use `atoi()` and `snprintf()` to

convert to and from numbers when performing arithmetic. It also does a 

lot of `strdup()`ing internally. The result is that that it could be too

slow for some tastes. Please don't hold it against me.

Another note: I have removed all checks on the return values of `malloc()` and 

friends functions to make the interpreter a little bit leaner. I would not 

recommend using the interpreter in environments where you may run out of memory.

I took some inspiration (like how the callframes are handled and several of the 

API functions) from Salvatore Sanfilippo's Picol Tcl interpreter, which can be 

found at http://antirez.com/page/picol. This is, however, a new implementation.

## Compile time flags and options

To make Fiz usable in different configurations, some compile time flags have

been added. Define these in your environment for the desired effect.

* `FIZ_DISABLE_INCLUDE_FILES` - disables `fiz_readfile` function, `include`

  command and the interactive shell. Provided for embedding into other 

  applications

* `FIZ_INTEGER_EXPR` - changes the floating point expression evaluation

  to use integers

These options are also available:

* `FIZ_OVERRIDE_HASH_DEFAULT_SIZE` - set to override default hash size (default 512)

*