Syntax

Syntax

Thagore uses Python-style indentation for blocks and a colon at the end of block-introducing lines. The parser is strict about layout and the lexer treats indentation errors as hard errors.

Indentation

Rules:

• indentation width is 2 spaces
• TAB characters are rejected by the lexer
• block headers end with :
• if and while conditions must be wrapped in parentheses

Valid:

func main() -> i32:
  let value: i32 = 3
  if (value > 0):
    return 0
  return 1

Invalid:

func main() -> i32:
   return 0

The second example uses 3 spaces and is rejected as invalid indentation.

Comments

Single-line comments start with #:

# this is a comment
func main():
  # comments can appear inside blocks
  println("ok")

Keywords

The current compiler recognizes these declaration and control-flow keywords directly:

Keyword	Role
let	local or top-level binding
const	top-level constant
func	function declaration
if	conditional branch
else	alternate branch
while	loop
for	loop over Array[T]
return	return from function
import	import declaration
from	selective import
extern	external function declaration
struct	nominal struct declaration
impl	method block
intent	intent declaration
flow	flow declaration
include	import ... include all form

The parser also recognizes these contextual keywords in specific positions:

Contextual keyword	Role
as	alias in imports
all	include all import form
pub	public export marker
break	loop exit
continue	next loop iteration
and	boolean conjunction
or	boolean disjunction
not	boolean negation
in	for item in items
stage, body, compensate, minimize	flow and intent bodies

Operators

The current parser uses Pratt precedence with the following order, from low to high:

Level	Operators
1	=
2	or
3	and
4	prefix not
5	==, !=
6	<, >, <=, >=
7	+, -
8	*, /, %
9	prefix -
10	., [], ()

Example:

func logic(a: i32, b: i32, c: i32, d: i32, e: i32, f: i32, g: i32):
  return a or b and not c == d < e + f * g

Statement forms

Top-level and block-level syntax is direct and explicit:

import std.math as math

const LIMIT: i32 = 5

func classify(value: i32) -> i32:
  if (value < 0):
    return 1
  else:
    return 0

Notes on unsupported surface

The current compiler does not implement elif as a separate keyword. Use nested if inside else instead:

func classify(value: i32) -> i32:
  if (value < 0):
    return 0
  else:
    if (value == 0):
      return 1
    else:
      return 2