Added spec version 0.1.

README.md

@@ -2,7 +2,7 @@
 
 Fun Uses Nothing - Life is too short not to code fun... ;)
 
-Influenced by C, Go, Lua, Python and Rust.
+Influenced by Bash, C, Go, Lua, Python and Rust.
 
 ## Idea
 

draft.fun

@@ -112,25 +112,23 @@ number foo = 23
 // Private variables can only be used here in this file.
 private number bar = 42
 
-for i in range(1, 1000) {
+for i in range(1, 1000)
-  echo i
+  print i
-  echo add(i, 1)
+  print add(i, 1)
-}
 
-for i in range(1, foo) {
+for i in range(1, foo)
-  echo "i"
+  print "i"
-}
 
 // This must not work since range() is an internal function.
 string range = "f987458n73v03258"
 
 if(x != y)
-  echo x
+  print x
 else if(a == b || h != i)
-  echo [a + b + h + i]
+  print [a + b + h + i]
 else
   if(k < 1 && l > 1)
-    echo "Buh!"
+    print "Buh!"
   fi
 fi
 
@@ -148,7 +146,8 @@ system(a)
 
 // Some kind of cast function for converting data types.
 cast(a)
-  return CASTED_string_to_another_existing_type(a)
+  // Not implemented.
+  return CASTED_variable_from_one_to_another_existing_type(a)
 
 // External functions need f as a prefix to define the function.
 f get_string(a_string, b_string)

spec/v0.1.md

@@ -0,0 +1,272 @@
+# Fun Language Specification v0.1
+
+**Fun (Fun Uses Nothing)** is a lightweight, multi-purpose programming language designed for clarity, safety, and—above all—fun.
+
+This document defines the language syntax and semantics as of version 0.1.
+
+## 1. Introduction
+
+Fun is a scripting and systems programming language inspired by the best ideas from C, Lua, and Python—yet deliberately strict in its rules to ensure readability and consistency.
+
+ - **Readable**: fixed indentation rules, no ambiguous syntax.
+ - **Strict**: type safety, no implicit coercion, no silent shadowing.
+ - **Hackable**: strong system integration with safe defaults.
+ - **Fun**: simple enough to learn in a day, expressive enough for real work.
+
+## 2. Lexical Structure
+
+### Case Sensitivity
+
+Fun is **case-sensitive**. `Fun` and `fun` are different identifiers.
+
+### Identifiers
+- May contain `a–z`, `A–Z`, `0–9`, and `_`.
+- Must not start with a number.
+
+### Keywords
+
+Reserved words cannot be redefined:
+`if`, `else`, `for`, `while`, `fi`, `f`, `global`, `private`, `return`, `true`, `false`.
+
+### Comments
+
+ - Single-line:
+// This is a comment
+ - Multi-line:
+/*
+  This is
+  a multi-line comment
+*/
+
+### Whitespace
+
+ - Indentation is exactly two spaces.
+ - Tabs are forbidden.
+ - Line breaks terminate statements (no semicolons).
+
+## 3. Data Types
+
+### Number
+
+ - 64-bit signed integer.
+
+```
+number n = 42
+```
+
+### Float
+
+ - 64-bit IEEE floating point.
+
+```
+float pi = 3.14159
+```
+
+### String
+
+ - Double or single quotes may be used.
+ - ' has higher priority, so " can appear unescaped inside '...'.
+ - To include ' inside '...', escape with \'.
+
+```
+string s1 = "Hello"
+string s2 = 'World'
+string s3 = "He said: 'Fun!'"
+```
+
+### Boolean
+
+ - Canonical values: true, false.
+ - 1 and 0 are accepted in conditionals.
+
+```
+boolean flag = true
+```
+
+### Byte
+
+ - Raw byte value.
+
+```
+byte b1 = 0x23
+byte b2 = "A"
+```
+
+### Array
+
+ - Declared using [ ... ].
+
+```
+array nums = [1, 2, 3]
+```
+
+## 4. Variables and Scope
+
+ - Global variables: accessible everywhere.
+ - Private variables: file-local, cannot be used outside the file.
+ - Redefining globals or shadowing names is forbidden.
+
+```
+global string message = "Hello"
+private number count = 42
+```
+
+## 5. Operators
+
+ - Arithmetic: + - * / %
+ - Comparison: == != > < >= <=
+ - Boolean: && || !
+ - Assignment: =
+
+## 6. Control Flow
+
+### If/Else
+
+```
+if(x != y)
+  print x
+else if(a == b || h != i)
+  print a + b
+else
+  if(k < 1 && l > 1)
+    print "Buh!"
+  fi
+fi
+```
+
+### For Loops
+
+```
+for i in range(1, 10)
+  print i
+```
+
+### While Loops
+
+```
+while x < 10
+  print x
+  x = x + 1
+```
+
+## 7. Functions
+
+### Internal Functions
+
+Provided by the runtime (cannot be redefined). Examples:
+print, range, system, exec.
+
+```
+print "Hello, Fun!"
+```
+
+### User-Defined Functions
+
+Must be declared with the f prefix.
+
+```
+f add(a, b)
+  return a + b
+```
+
+### Return Values
+
+ - Scalars: return a + b
+ - Arrays: return [a, b, c]
+
+## 8. Modules & Includes
+
+### System Includes
+
+Looked up in /var/lib/fun/, supporting .so (native) and .fun (Fun code).
+
+```
+&#35;include crypt/md5
+&#35;include date
+&#35;include math
+```
+
+### Local Includes
+
+From the current working directory:
+
+```
+&#35;include utils/file.fun
+```
+
+### Absolute Includes
+
+Full path:
+
+```
+&#35;include /home/user/project/lib.fun
+```
+
+## 9. System Integration
+
+### system
+
+Executes a command, returns exit code.
+
+```
+system("ls -l")
+```
+
+### exec
+
+Executes a command, returns stdout.
+
+```
+string result = exec("date")
+```
+
+### spawn
+
+Executes a command asynchronously, returns process ID.
+
+```
+number pid = spawn("sleep 10")
+```
+
+## 10. Error Handling
+
+ - No implicit type coercion.
+ - Redefinition of globals is a compile-time error.
+ - Using undefined variables or functions is an error.
+ - Internal/runtime functions cannot be shadowed.
+
+## 11. Examples
+
+### Hello World
+
+```
+print "Hello, World!"
+```
+
+### Loop with Range
+
+```
+for i in range(1, 5)
+  print i
+```
+
+### User Function
+
+```
+f greet(name)
+  return "Hello " + name
+
+print greet("Fun")
+```
+
+### System Call
+
+```
+string now = exec("date")
+print "Current time: " + now
+```
+
+## 12. License
+
+This document and the Fun language reference are licensed under the Apache License 2.0
+