⬡ MiniLang Compiler IDE

A from-scratch compiler IDE for the MiniLang programming language (.mlg) — a custom-designed language with its own hand-written scanner, recursive predictive parser, and tree-walk interpreter. Built entirely with Python & tkinter, zero external dependencies.

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📸 Features at a Glance

Feature	Description
Lexer	Hand-written state-machine scanner, no re module
Parser	Recursive Predictive Parser (LL(1))
Parse Tree	TreeView text tree + Canvas graphical drawing
Interpreter	Tree-walk executor with real input() dialogs
IDE	Modern dark GUI with syntax highlighting

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🚀 Getting Started

Requirements

• Python 3.8+
• tkinter (included with standard Python on Windows & Linux)

Run

python minilang_compiler.py

No pip installs needed — zero external dependencies.

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🗂️ Project Structure

MiniLang-Compiler/
├── minilang_compiler.py   ← main file (run this)
├── MiniLang_Spec.md       ← full language specification
├── examples/
│   ├── hello.mlg          ← hello world
│   ├── loops.mlg          ← for loop examples
│   └── comparisons.mlg    ← comparison operators
└── README.md

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📝 MiniLang Quick Syntax

// variables
x = 42
pi = 3.14
msg = "hello"

// if / else
IF (x > 0) :
{
    print(x)
}
else
{
    print(msg)
}

// for loop
for (i = 0 , i < 10 , i++)
{
    x = x + 1
}

// method
method add(a, b) :
{
    c = a + b
}

// print & input
print(x)
input(y)

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⚙️ How It Works

Lexer / Scanner

Recognizes all tokens using explicit state machines:

State Machine	Tokens Produced
Whitespace (states 22–24)	skipped
Identifier / Keyword (states 9–11)	ID, KW
Unsigned Numbers (states 12–21)	INTEGER, FLOAT, SCIENTIFIC
String literal (S0–S2)	STRING
Relational Operators (R0–R8)	EQ NEQ LT GT LEQ GEQ
Arithmetic & symbols	PLUS STAR ASSIGN PLUSPLUS …

Output → Lexical Table: Token | Type | Line | Col

Recursive Predictive Parser

Grammar is LL(1) — no left recursion, no backtracking. Each non-terminal maps to exactly one function:

Program    → Statement*
Statement  → Assignment | IfStatement | ForLoop | ...
Expression → ArithExpr [ relop ArithExpr ]
ArithExpr  → Term { + Term }
Term       → Factor { * Factor }
Factor     → INTEGER | FLOAT | SCIENTIFIC | STRING | ID

Output → Parse Tree (TreeView) + Visual Canvas Tree

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🎨 IDE Features

• Syntax Highlighting — debounced (250 ms), never freezes
• Line Numbers gutter
• File Operations — New / Open / Save / Save As (.mlg filter)
• Keyboard Shortcuts — F5 Compile · F6 Run · Ctrl+S Save · Ctrl+H Find & Replace · Ctrl+Z/Y Undo/Redo
• Error Highlighting — first error line turns red in editor
• Visual Parse Tree — colour-coded Canvas drawing with scroll
• Interpreter — executes the AST, real input() popup dialog

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📚 Token Reference

Token	Example	Colour
Keyword	IF for print	Violet
Integer	42	Orange
Float	3.14	Orange
Scientific	1.5E+10	Orange
String	"hello"	Green
Comparison	== != < <= > >=	Pink
Operator	+ * = ++	Cyan

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📄 License

MIT — free to use and modify.