help function displays values not

Signed-off-by: Ava Hahn <ava@aidanis.online>

src/stl/control.rs

@@ -19,6 +19,15 @@ use crate::eval::eval;
 use crate::segment::{Ctr, Seg};
 use crate::sym::{Args, SymTable, Symbol, ValueType};
 
+pub const IF_DOCSTRING: &str = "accepts three bodies, a condition, an unevaluated consequence, and an alternative consequence.
+If the condition is evaluated to true, the first consequence is evaluated.
+If the condition is evaluated to false, the second consequence is evaluated.
+Otherwise, an error is thrown.
+
+example: (if my-state-switch
+           (do-my-thing)
+           (else-an-other-thing))";
+
 pub fn if_callback(ast: &Seg, syms: &mut SymTable) -> Result<Ctr, String> {
     let cond: bool;
     println!("Y: {}", *ast.car);
@@ -85,6 +94,20 @@ pub fn if_callback(ast: &Seg, syms: &mut SymTable) -> Result<Ctr, String> {
     }
 }
 
+pub const LET_DOCSTRING: &str =  "creates a stack of local variables for a sequence of operations.
+returns the result of the final operation.
+
+example: (let ((step1 'hello')
+               (step2 (concat step1 '-'))
+               (step3 (concat step2 'world')))
+              (echo step3)
+              (some-func some-args))
+
+In this example step1, step2, and step3 are created sequentially.
+Then, the echo form is evaluated, printing 'hello-world'.
+Finally, the some-func form is evaluated.
+Since the call to some-func is the final form, its value is returned.";
+
 pub fn let_callback(ast: &Seg, syms: &mut SymTable) -> Result<Ctr, String> {
     let mut localsyms = syms.clone();
     let locals_form: &Seg;
@@ -180,9 +203,14 @@ pub fn let_callback(ast: &Seg, syms: &mut SymTable) -> Result<Ctr, String> {
     Ok((*result).clone())
 }
 
-/*
-(while (cond) evalme evalme evalme evalme ... )
- */
+pub const WHILE_DOCSTRING: &str = "traverses a list of N un-evaluated forms.
+the first form is expected to evaluate to a boolean. if it evaluates to false, while will stop and return. Otherwise, while will evaluate each form in a loop.
+
+example: (while (check-my-state)
+                (do-thing-1 args)
+                (do-thing-2 args)
+                (edit-state my-state))";
+
 pub fn while_callback(ast: &Seg, syms: &mut SymTable) -> Result<Ctr, String> {
     let eval_cond: &Seg;
     let outer_maybe: Seg;
@@ -244,9 +272,17 @@ pub fn while_callback(ast: &Seg, syms: &mut SymTable) -> Result<Ctr, String> {
     Ok(*(result.unwrap()).clone())
 }
 
-/*
-(circuit makes_a_bool makes_a_bool makes_a_bool makes_a_bool ... )
-*/
+pub const CIRCUIT_DOCSTRING: &str = "traverses a list of N un-evaluated forms.
+evaluates each one until it stops. Circuit will stop when a form errors during evaluation.
+Circuit will also stop when a form does not evaluate to a boolean, or evaluates to false.
+
+example: (circuit (eq? (do-operation) myresult)
+                  (and state1 state2 (boolean-operation3))
+                  false
+                  (do-another-operation))
+
+in this example, do-another-operation will not be called";
+
 pub fn circuit_callback(ast: &Seg, syms: &mut SymTable) -> Result<Ctr, String> {
     let mut cursor = 0;
     let mut error: String = String::new();