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extern crate test;
use std::cmp::{Ordering};
use std::fmt;
use std::hash;
use environment::{Activation, RootedActivationPtr};
use heap::{Heap, Rooted};
use read::{Location};
use value::{RootedValue, SchemeResult, Value};
pub fn evaluate(heap: &mut Heap, form: &RootedValue, location: Location) -> SchemeResult {
let meaning = try!(analyze(heap, form, location));
let mut act = heap.global_activation();
meaning.evaluate(heap, &mut act)
}
pub fn evaluate_file(heap: &mut Heap, file_path: &str) -> SchemeResult {
use read::read_from_file;
let reader = match read_from_file(file_path, heap) {
Ok(r) => r,
Err(e) => {
return Err(format!("Error: evaluate_file could not read {}: {}",
file_path,
e));
},
};
let mut result = Rooted::new(heap, Value::EmptyList);
for (location, read_result) in reader {
let form = try!(read_result);
result.emplace(*try!(evaluate(heap, &form, location)));
}
return Ok(result);
}
#[derive(Debug)]
pub enum Trampoline {
Value(RootedValue),
Thunk(RootedActivationPtr, Meaning),
}
impl Trampoline {
pub fn run(self, heap: &mut Heap) -> SchemeResult {
match self {
Trampoline::Value(v) => {
return Ok(v);
},
Trampoline::Thunk(act, meaning) => {
let mut a = act;
let mut m = meaning;
loop {
match try!(m.evaluate_to_thunk(heap, &mut a)) {
Trampoline::Value(v) => {
return Ok(v);
},
Trampoline::Thunk(aa, mm) => {
a = aa;
m = mm;
},
}
}
}
}
}
}
pub type TrampolineResult = Result<Trampoline, String>;
#[derive(Clone, Hash, Debug)]
enum MeaningData {
Quotation(RootedValue),
Reference(u32, u32, String),
Definition(u32, u32, Meaning),
SetVariable(u32, u32, Meaning),
Conditional(Meaning, Meaning, Meaning),
Sequence(Meaning, Meaning),
Lambda(u32, Meaning),
Invocation(Meaning, Vec<Meaning>),
}
impl fmt::Display for MeaningData {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
MeaningData::Quotation(ref val) => {
write!(f, "(quotation {})", **val)
},
MeaningData::Reference(i, j, ref name) => {
write!(f, "(reference {} {} {})", i, j, name)
},
MeaningData::Definition(i, j, ref val) => {
write!(f, "(definition {} {} {})", i, j, val)
},
MeaningData::SetVariable(i, j, ref val) => {
write!(f, "(set-variable {} {} {})", i, j, val)
},
MeaningData::Conditional(ref condition,
ref consequent,
ref alternative) => {
write!(f, "(conditional {} {} {})",
condition,
consequent,
alternative)
},
MeaningData::Sequence(ref first, ref second) => {
write!(f, "(sequence {} {})", first, second)
},
MeaningData::Lambda(arity, ref body) => {
write!(f, "(lambda {} {})", arity, body)
},
MeaningData::Invocation(ref procedure, ref arguments) => {
try!(write!(f, "(invocation {} [", procedure));
let mut is_first = true;
for arg in arguments.iter() {
try!(write!(f, "{}{}", if is_first { "" } else { " " }, arg));
is_first = false;
}
write!(f, "])")
},
}
}
}
type MeaningEvaluatorFn = fn(&mut Heap,
&MeaningData,
&mut RootedActivationPtr) -> TrampolineResult;
impl fmt::Debug for MeaningEvaluatorFn {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "0x{:x}", *self as usize)
}
}
#[allow(unused_variables)]
fn evaluate_quotation(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::Quotation(ref val) = *data {
return Ok(Trampoline::Value(Rooted::new(heap, **val)));
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
fn evaluate_reference(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::Reference(i, j, ref name) = *data {
let val = try!(act.fetch(heap, i, j).ok().ok_or(
format!("Reference to variable that hasn't been defined: {}", name)));
return Ok(Trampoline::Value(val));
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
fn evaluate_definition(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::Definition(i, j, ref definition_value_meaning) = *data {
debug_assert!(i == 0,
"Definitions should always be in the youngest activation");
let val = try!(definition_value_meaning.evaluate(heap, act));
act.define(j, *val);
return Ok(Trampoline::Value(heap.unspecified_symbol()));
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
fn evaluate_set_variable(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::SetVariable(i, j, ref definition_value_meaning) = *data {
let val = try!(definition_value_meaning.evaluate(heap, act));
try!(act.update(i, j, &val).ok().ok_or(
"Cannot set variable before it has been defined".to_string()));
return Ok(Trampoline::Value(heap.unspecified_symbol()));
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
fn evaluate_conditional(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::Conditional(ref condition,
ref consequent,
ref alternative) = *data {
let val = try!(condition.evaluate(heap, act));
return Ok(Trampoline::Thunk(Rooted::new(heap, **act),
if *val == Value::new_boolean(false) {
(*alternative).clone()
} else {
(*consequent).clone()
}));
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
fn evaluate_sequence(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::Sequence(ref first, ref second) = *data {
try!(first.evaluate(heap, act));
return Ok(Trampoline::Thunk(Rooted::new(heap, **act), second.clone()));
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
fn evaluate_lambda(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::Lambda(arity, ref body) = *data {
return Ok(Trampoline::Value(
Value::new_procedure(heap, arity, act, (*body).clone())));
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
pub fn apply_invocation(heap: &mut Heap,
proc_val: &RootedValue,
args: Vec<RootedValue>) -> TrampolineResult {
match **proc_val {
Value::Primitive(primitive) => {
return primitive.call(heap, args);
},
Value::Procedure(proc_ptr) => {
match proc_ptr.arity.cmp(&(args.len() as u32)) {
Ordering::Less => {
return Err("Error: too many arguments passed".to_string());
},
Ordering::Greater => {
return Err("Error: too few arguments passed".to_string());
},
_ => {
let proc_act = proc_ptr.act.as_ref()
.expect("Should never see an uninitialized procedure!");
let rooted_proc_act = Rooted::new(heap, *proc_act);
let body = proc_ptr.body.as_ref()
.expect("Should never see an uninitialized procedure!");
let new_act = Activation::extend(heap,
&rooted_proc_act,
args);
return Ok(Trampoline::Thunk(new_act, (**body).clone()));
},
}
},
_ => {
return Err(format!("Error: expected a procedure to call, found {}",
**proc_val));
}
}
}
fn evaluate_invocation(heap: &mut Heap,
data: &MeaningData,
act: &mut RootedActivationPtr) -> TrampolineResult {
if let MeaningData::Invocation(ref procedure, ref params) = *data {
let proc_val = try!(procedure.evaluate(heap, act));
let args = try!(params.iter().map(|p| p.evaluate(heap, act)).collect());
return apply_invocation(heap, &proc_val, args);
}
panic!("unsynchronized MeaningData and MeaningEvaluatorFn");
}
#[derive(Debug)]
pub struct Meaning {
data: Box<MeaningData>,
evaluator: MeaningEvaluatorFn,
location: Location,
}
impl Meaning {
fn new_quotation(form: &RootedValue, location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::Quotation((*form).clone())),
evaluator: evaluate_quotation,
location: location
}
}
fn new_reference(i: u32, j: u32, name: String, location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::Reference(i, j, name)),
evaluator: evaluate_reference,
location: location
}
}
fn new_set_variable(i: u32, j: u32, val: Meaning, location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::SetVariable(i, j, val)),
evaluator: evaluate_set_variable,
location: location,
}
}
fn new_conditional(condition: Meaning,
consquent: Meaning,
alternative: Meaning,
location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::Conditional(condition,
consquent,
alternative)),
evaluator: evaluate_conditional,
location: location,
}
}
fn new_sequence(first: Meaning, second: Meaning, location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::Sequence(first, second)),
evaluator: evaluate_sequence,
location: location,
}
}
fn new_definition(i: u32, j: u32, defined: Meaning, location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::Definition(i, j, defined)),
evaluator: evaluate_definition,
location: location,
}
}
fn new_lambda(arity: u32, body: Meaning, location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::Lambda(arity, body)),
evaluator: evaluate_lambda,
location: location,
}
}
fn new_invocation(procedure: Meaning, params: Vec<Meaning>, location: Location) -> Meaning {
Meaning {
data: Box::new(MeaningData::Invocation(procedure, params)),
evaluator: evaluate_invocation,
location: location
}
}
}
impl Meaning {
#[inline]
fn evaluate_to_thunk(&self,
heap: &mut Heap,
act: &mut RootedActivationPtr) -> TrampolineResult {
match (self.evaluator)(heap, &*self.data, act) {
Err(e) => Err(format!("{}:\n{}", self.location, e)),
ok => ok
}
}
fn evaluate(&self,
heap: &mut Heap,
act: &mut RootedActivationPtr) -> SchemeResult {
let thunk = try!(self.evaluate_to_thunk(heap, act));
thunk.run(heap)
}
}
impl Clone for Meaning {
fn clone(&self) -> Self {
Meaning {
data: self.data.clone(),
evaluator: self.evaluator,
location: self.location.clone(),
}
}
}
impl fmt::Display for Meaning {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", *self.data)
}
}
impl<S: hash::Writer + hash::Hasher> hash::Hash<S> for Meaning {
fn hash(&self, state: &mut S) {
let u = self.evaluator as usize;
u.hash(state);
self.data.hash(state);
}
}
pub type MeaningResult = Result<Meaning, String>;
pub fn analyze(heap: &mut Heap,
form: &RootedValue,
location: Location) -> MeaningResult {
if form.is_atom() {
return analyze_atom(heap, form, location);
}
let pair = form.to_pair(heap).expect(
"If a value is not an atom, then it must be a pair.");
let quote = heap.quote_symbol();
let if_symbol = heap.if_symbol();
let begin = heap.begin_symbol();
let define = heap.define_symbol();
let set_bang = heap.set_bang_symbol();
let lambda = heap.lambda_symbol();
match *pair.car(heap) {
v if v == *quote => analyze_quoted(heap, form),
v if v == *define => analyze_definition(heap, form),
v if v == *set_bang => analyze_set(heap, form),
v if v == *lambda => analyze_lambda(heap, form),
v if v == *if_symbol => analyze_conditional(heap, form),
v if v == *begin => analyze_sequence(heap, form),
_ => analyze_invocation(heap, form),
}
}
fn is_auto_quoting(form: &RootedValue) -> bool {
match **form {
Value::EmptyList => false,
Value::Pair(_) => false,
Value::Symbol(_) => false,
_ => true,
}
}
fn analyze_atom(heap: &mut Heap,
form: &RootedValue,
location: Location) -> MeaningResult {
if is_auto_quoting(form) {
return Ok(Meaning::new_quotation(form, location));
}
if let Some(sym) = form.to_symbol(heap) {
if let Some((i, j)) = heap.environment.lookup(&**sym) {
return Ok(Meaning::new_reference(i, j, (**sym).clone(), location));
}
let (i, j) = heap.environment.define_global((**sym).clone());
return Ok(Meaning::new_reference(i, j, (**sym).clone(), location));
}
return Err(format!("Static error: Cannot evaluate: {}", **form));
}
fn analyze_quoted(heap: &mut Heap, form: &RootedValue) -> MeaningResult {
if let Ok(2) = form.len() {
let pair = form.to_pair(heap).unwrap();
return Ok(Meaning::new_quotation(
&form.cdr(heap).unwrap().car(heap).unwrap(),
heap.locate(&pair)));
}
let msg = "Static error: Wrong number of parts in quoted form";
Err(if let Some(pair) = form.to_pair(heap) {
format!("{}: {}", heap.locate(&pair), msg)
} else {
msg.to_string()
})
}
fn analyze_definition(heap: &mut Heap,
form: &RootedValue) -> MeaningResult {
if let Ok(3) = form.len() {
let pair = form.to_pair(heap).expect(
"If len = 3, then form must be a pair");
let sym = try!(pair.cadr(heap));
let location = heap.locate(&pair);
if let Some(str) = sym.to_symbol(heap) {
let def_value_form = try!(pair.caddr(heap));
let def_value_meaning = try!(analyze(heap,
&def_value_form,
location.clone()));
let (i, j) = heap.environment.define((**str).clone());
return Ok(Meaning::new_definition(i, j, def_value_meaning, location));
}
return Err(format!("{}: Static error: can only define symbols, found: {}",
location,
*sym));
}
let msg = "Static error: improperly formed definition";
Err(if let Some(pair) = form.to_pair(heap) {
format!("{}: {}: {}", heap.locate(&pair), msg, **form)
} else {
format!("{}: {}", msg, **form)
})
}
fn analyze_set(heap: &mut Heap,
form: &RootedValue) -> MeaningResult {
if let Ok(3) = form.len() {
let pair = form.to_pair(heap).expect(
"If len = 3, then form must be a pair");
let sym = try!(pair.cadr(heap));
let location = heap.locate(&pair);
if let Some(str) = sym.to_symbol(heap) {
let set_value_form = try!(pair.caddr(heap));
let set_value_meaning = try!(analyze(heap,
&set_value_form,
location.clone()));
if let Some((i, j)) = heap.environment.lookup(&**str) {
return Ok(Meaning::new_set_variable(i,
j,
set_value_meaning,
location));
}
let (i, j) = heap.environment.define_global((**str).clone());
return Ok(Meaning::new_set_variable(i,
j,
set_value_meaning,
location));
}
return Err(format!("{}: Static error: can only set! symbols, found: {}",
location,
*sym));
}
let msg = "Static error: improperly formed set!";
Err(if let Some(pair) = form.to_pair(heap) {
format!("{}: {}: {}", heap.locate(&pair), msg, **form)
} else {
format!("{}: {}", msg, **form)
})
}
fn analyze_lambda(heap: &mut Heap,
form: &RootedValue) -> MeaningResult {
let length = try!(form.len().ok().ok_or_else(|| {
let msg = "Static error: improperly formed lambda";
if let Some(pair) = form.to_pair(heap) {
format!("{}: {}: {}", heap.locate(&pair), msg, **form)
} else {
format!("{}: {}", msg, **form)
}
}));
if length < 3 {
let msg = "Static error: improperly formed lambda";
return Err(if let Some(pair) = form.to_pair(heap) {
format!("{}: {}: {}", heap.locate(&pair), msg, **form)
} else {
format!("{}: {}", msg, **form)
})
}
let pair = form.to_pair(heap).unwrap();
let location = heap.locate(&pair);
let body = pair.cddr(heap)
.ok().expect("Must be here since length >= 3");
let mut params = vec!();
let mut arity = 0;
let params_form = pair.cadr(heap).ok().expect(
"Must be here since length >= 3");
for p in params_form.iter() {
arity += 1;
params.push(try!(p.ok().ok_or(format!("{}: Bad lambda parameters: {}",
location,
*params_form))));
}
let mut param_names : Vec<String> = try!(params.into_iter().map(|p| {
let sym = try!(p.to_symbol(heap)
.ok_or(format!("{}: Can only define symbol parameters, found {}",
location,
p)));
Ok((**sym).clone())
}).collect());
let define = heap.define_symbol();
let mut local_definitions : Vec<String> = body.iter()
.filter_map(|form_result| {
if let Ok(form) = form_result {
if let Some(pair) = form.to_pair(heap) {
if pair.car(heap) == define {
if let Ok(name) = pair.cadr(heap) {
return name.to_symbol(heap).map(|s| (**s).clone())
}
}
}
}
None
})
.collect();
let mut new_bindings = Vec::with_capacity(param_names.len() + local_definitions.len());
new_bindings.append(&mut param_names);
new_bindings.append(&mut local_definitions);
let body_meaning = try!(heap.with_extended_env(new_bindings, &|heap| {
make_meaning_sequence(heap, &body)
}));
return Ok(Meaning::new_lambda(arity as u32, body_meaning, location));
}
fn analyze_conditional(heap: &mut Heap,
form: &RootedValue) -> MeaningResult {
if let Ok(4) = form.len() {
let pair = form.to_pair(heap).expect(
"If len = 4, then form must be a pair");
let location = heap.locate(&pair);
let condition_form = try!(pair.cadr(heap));
let condition_meaning = try!(analyze(heap,
&condition_form,
location.clone()));
let consequent_form = try!(pair.caddr(heap));
let consequent_meaning = try!(analyze(heap,
&consequent_form,
location.clone()));
let alternative_form = try!(pair.cadddr(heap));
let alternative_meaning = try!(analyze(heap,
&alternative_form,
location.clone()));
return Ok(Meaning::new_conditional(condition_meaning,
consequent_meaning,
alternative_meaning,
location));
}
let msg = "Static error: improperly if expression";
Err(if let Some(pair) = form.to_pair(heap) {
format!("{}: {}: {}", heap.locate(&pair), msg, **form)
} else {
format!("{}: {}", msg, **form)
})
}
fn make_meaning_sequence(heap: &mut Heap,
forms: &RootedValue) -> MeaningResult {
if let Some(ref cons) = forms.to_pair(heap) {
let first_form = cons.car(heap);
let location = heap.locate(cons);
let first = try!(analyze(heap, &first_form, location.clone()));
if *cons.cdr(heap) == Value::EmptyList {
return Ok(first);
} else {
let rest_forms = cons.cdr(heap);
let rest = try!(make_meaning_sequence(heap, &rest_forms));
return Ok(Meaning::new_sequence(first, rest, location));
}
}
Err(format!("Static error: improperly formed sequence: {}", **forms))
}
fn analyze_sequence(heap: &mut Heap,
form: &RootedValue) -> MeaningResult {
let forms = try!(form.cdr(heap).ok_or(
format!("Static error: improperly formed sequence: {}", **form)));
make_meaning_sequence(heap, &forms)
}
fn make_meaning_vector(heap: &mut Heap,
forms: &RootedValue,
mut meanings: Vec<Meaning>) -> Result<Vec<Meaning>, String> {
match **forms {
Value::EmptyList => Ok(meanings),
Value::Pair(ref cons) => {
let car = cons.car(heap);
let rest = cons.cdr(heap);
let pair = forms.to_pair(heap).unwrap();
let location = heap.locate(&pair);
meanings.push(try!(analyze(heap,
&car,
location)));
make_meaning_vector(heap, &rest, meanings)
},
_ => {
panic!("Passed improper list to `make_meaning_vector`!");
}
}
}
fn analyze_invocation(heap: &mut Heap,
form: &RootedValue) -> MeaningResult {
if let Some(ref cons) = form.to_pair(heap) {
let location = heap.locate(cons);
let proc_form = cons.car(heap);
let proc_meaning = try!(analyze(heap, &proc_form, location.clone()));
let params_form = cons.cdr(heap);
let arity = try!(params_form.len().ok().ok_or(
"Static error: improperly formed invocation".to_string()));
let params_meaning = try!(make_meaning_vector(
heap, ¶ms_form, Vec::with_capacity(arity as usize)));
return Ok(Meaning::new_invocation(proc_meaning, params_meaning, location));
}
return Err(format!("Static error: improperly formed invocation: {}", **form));
}
#[cfg(test)]
mod tests {
use super::*;
use heap::{Heap, Rooted};
use read::{Location};
use value::{list, Value};
#[test]
fn test_eval_integer() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_integer.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(42));
}
#[test]
fn test_eval_boolean() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_boolean.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_boolean(true));
}
#[test]
fn test_eval_quoted() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_quoted.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::EmptyList);
}
#[test]
fn test_eval_if_consequent() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_if_consequent.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(1));
}
#[test]
fn test_eval_if_alternative() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_if_alternative.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(2));
}
#[test]
fn test_eval_begin() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_begin.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(2));
}
#[test]
fn test_eval_variables() {
let heap = &mut Heap::new();
let define_symbol = heap.define_symbol();
let set_bang_symbol = heap.set_bang_symbol();
let foo_symbol = heap.get_or_create_symbol("foo".to_string());
let mut def_items = [
define_symbol,
foo_symbol,
Rooted::new(heap, Value::new_integer(2))
];
let def_form = list(heap, &mut def_items);
evaluate(heap, &def_form, Location::unknown()).ok()
.expect("Should be able to define");
let foo_symbol_ = heap.get_or_create_symbol("foo".to_string());
let def_val = evaluate(heap, &foo_symbol_, Location::unknown()).ok()
.expect("Should be able to get a defined symbol's value");
assert_eq!(*def_val, Value::new_integer(2));
let mut set_items = [
set_bang_symbol,
foo_symbol_,
Rooted::new(heap, Value::new_integer(1))
];
let set_form = list(heap, &mut set_items);
evaluate(heap, &set_form, Location::unknown()).ok()
.expect("Should be able to define");
let foo_symbol__ = heap.get_or_create_symbol("foo".to_string());
let set_val = evaluate(heap, &foo_symbol__, Location::unknown()).ok()
.expect("Should be able to get a defined symbol's value");
assert_eq!(*set_val, Value::new_integer(1));
}
#[test]
fn test_eval_and_call_lambda() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_and_call_lambda.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(5));
}
#[test]
fn test_eval_closures() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_eval_closures.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(1));
}
#[test]
fn test_ref_defined_later() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_ref_defined_later.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(1));
}
#[test]
fn test_set_defined_later() {
let mut heap = Heap::new();
let result = evaluate_file(&mut heap, "./tests/test_set_defined_later.scm")
.ok()
.expect("Should be able to eval a file.");
assert_eq!(*result, Value::new_integer(5));
}
#[test]
fn test_rooting_bug() {
let mut heap = Heap::new();
evaluate_file(&mut heap, "./tests/rooting-bug.scm")
.ok()
.expect("Should be able to eval a file.");
assert!(true, "Should be able to evaluate that file without panicking.");
}
#[test]
fn test_eval_local_definitions() {
let mut heap = Heap::new();
match evaluate_file(&mut heap, "./tests/test_eval_local_definitions.scm") {
Err(msg) => panic!(msg),
Ok(result) => assert_eq!(*result, Value::new_integer(120)),
}
}
}
#[cfg(test)]
mod bench {
use super::*;
use super::test::{Bencher};
use heap::{Heap, Rooted};
use read::{Location};
use value::{list, Value};
#[bench]
fn bench_iterate_empty_loops(b: &mut Bencher) {
let mut heap = Heap::new();
let iter_fn = evaluate_file(&mut heap, "./tests/bench_iterate_empty_loops.scm")
.ok()
.expect("Should be able to eval a file.");
b.iter(|| {
let mut call_items = [
iter_fn.clone(),
Rooted::new(&mut heap, Value::new_integer(10000))
];
let call = list(&mut heap, &mut call_items);
evaluate(&mut heap, &call, Location::unknown()).ok()
.expect("Should be able to call our function");
});
}
#[bench]
fn bench_allocate_cons_cells(b: &mut Bencher) {
let mut heap = Heap::new();
let alloc_fn = match evaluate_file(&mut heap, "./tests/bench_allocate_cons_cells.scm") {
Ok(v) => v,
Err(msg) => panic!(msg)
};
let quote = heap.quote_symbol();
let empty_list = Rooted::new(&mut heap, Value::EmptyList);
b.iter(|| {
let mut call_items = [
alloc_fn.clone(),
Rooted::new(&mut heap, Value::new_integer(10000)),
list(&mut heap, &mut [quote.clone(), empty_list.clone()])
];
let call = list(&mut heap, &mut call_items);
match evaluate(&mut heap, &call, Location::unknown()) {
Err(msg) => panic!(msg),
_ => { }
};
});
}
#[bench]
fn bench_eval_metacircular(b: &mut Bencher) {
let heap = &mut Heap::new();
let eval_fib_call = match evaluate_file(heap, "./tests/bench_eval_metacircular.scm") {
Ok(v) => v,
Err(msg) => panic!(msg)
};
b.iter(|| {
match evaluate(heap, &eval_fib_call.clone(), Location::unknown()) {
Err(msg) => panic!(msg),
_ => { },
};
});
}
}