Let bindings are technically done, but until lambdas can capture thei…

…r environment they will not work

DOCUMENTATION.md

@@ -51,6 +51,9 @@
 #### `lambda`
 - Constructs an anonymous function with two parts: a parameter list and a body. Here's an example: `(lambda (x y) (+ x y))`
 
+#### `let`
+- These are a work in progress.
+
 #### `quote`
 - Converts a string into a compile-time constant hash that can be used for quick comparisons via `eq?`. The resulting symbol is uninterned and has no print name.
 

src/compiler.py

@@ -285,7 +285,7 @@ def main(infile, outfile, extern):
 Working on right now:
 - finding a new GC or providing other flags to make it behave differently?
 - printing nil from display_list
-- let bindings?
+- let bindings
 
 Function val error:
 (define nums (cons 1 (cons 2 3)))

tests/bugs.lisp

@@ -7,4 +7,11 @@
 	(begin
 		(display_char #\()
 		(_display_list x)))
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Incorrect results:
+(define (g a) (let ((b 3) (c 4)) (* a (* b c))))
+(display (g 2))
+(newline)
+
+(define (f a) ((lambda (b c) (* a (* b c))) 3 4))
+(display (f 2)); weird! both are wrong. both are 36 when they should be 24.
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

tests/test.asm

@@ -22,11 +22,7 @@ f:
 	anonymous_1:
 	push rbp
 	mov rbp, rsp
-	push [rbp + 24]  # push argument to *
 	push [rbp + 16]  # push argument to *
-	call multiply
-	add rsp, 16  # discard 2 local arguments
-	push rax  # result of *
 	push [rbp + 16]  # push argument to *
 	call multiply
 	add rsp, 16  # discard 2 local arguments
@@ -35,10 +31,9 @@ f:
 	ret
 	after_anonymous_1:
 	lea rax, [anonymous_1 + rip]
-	push 4  # push argument to rax
 	push 3  # push argument to rax
 	call rax
-	add rsp, 16  # discard 2 local arguments
+	add rsp, 8  # discard 1 local argument
 	mov rsp, rbp
 	pop rbp
 	ret

tests/test.lisp

@@ -1,4 +1,11 @@
-(define (f a)
-	(let ((b 3) (c 4))
-		(* a (* b c))))
-(display (f 2)); wrong result! is 36, should be 
+|
+(define (g a) (let ((b 3)) (* a b)))
+(display (g 2))
+(newline)
+|
+
+(define (f a) ((lambda (b) (* a b)) 3))
+(display (f 2)); Weird! Both are wrong. Both are 9 when they should be 6.
+; For this to work, that lambda has to be able to capture its surrounding environment.
+; 1. How would it do that?
+; 2. What is making it behave not as expected right now? (or why is it squaring the first argument?)