feat: add Float.nearly_eq

GreasySlug · Nov 6, 2023 · ebf803d · ebf803d
1 parent b87c075
commit ebf803d
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Showing 4 changed files with 36 additions and 8 deletions.
diff --git a/crates/erg_compiler/context/hint.rs b/crates/erg_compiler/context/hint.rs
@@ -134,28 +134,36 @@ impl Context {
                 switch_lang!(
                     "japanese" => {
                         hint.push_str("Floatは等価関係が定義されていません。");
-                        hint.push_str_with_color_and_attr("l == R", ERR, ATTR);
+                        hint.push_str_with_color_and_attr("l == r", ERR, ATTR);
                         hint.push_str("ではなく、");
                         hint.push_str_with_color_and_attr("l - r <= Float.EPSILON", HINT, ATTR);
+                        hint.push_str("あるいは");
+                        hint.push_str_with_color_and_attr("l.nearly_eq(r)", HINT, ATTR);
                         hint.push_str("を使用してください");
                     },
                     "simplified_chinese" => {
                         hint.push_str("Float没有定义等价关系。你应该使用");
-                        hint.push_str_with_color_and_attr("l == R", ERR, ATTR);
-                        hint.push_str("而不是");
                         hint.push_str_with_color_and_attr("l - r <= Float.EPSILON", HINT, ATTR);
+                        hint.push_str("或者");
+                        hint.push_str_with_color_and_attr("l.nearly_eq(r)", HINT, ATTR);
+                        hint.push_str("而不是");
+                        hint.push_str_with_color_and_attr("l == r", ERR, ATTR);
                     },
                     "traditional_chinese" => {
                         hint.push_str("Float沒有定義等價關係。你應該使用");
-                        hint.push_str_with_color_and_attr("l == R", ERR, ATTR);
-                        hint.push_str(" instead of ");
                         hint.push_str_with_color_and_attr("l - r <= Float.EPSILON", HINT, ATTR);
+                        hint.push_str("或者");
+                        hint.push_str_with_color_and_attr("l.nearly_eq(r)", HINT, ATTR);
+                        hint.push_str("而不是");
+                        hint.push_str_with_color_and_attr("l == r", ERR, ATTR);
                     },
                     "english" => {
-                        hint.push_str("Float has no equivalence relation defined. you should use ");
-                        hint.push_str_with_color_and_attr("l == R", ERR, ATTR);
-                        hint.push_str(" instead of ");
+                        hint.push_str("Float has no equivalence relation defined. You should use ");
                         hint.push_str_with_color_and_attr("l - r <= Float.EPSILON", HINT, ATTR);
+                        hint.push_str(" or ");
+                        hint.push_str_with_color_and_attr("l.nearly_eq(r)", HINT, ATTR);
+                        hint.push_str(" instead of ");
+                        hint.push_str_with_color_and_attr("l == r", ERR, ATTR);
                     },
                 );
                 Some(hint.to_string())

diff --git a/crates/erg_compiler/context/initialize/classes.rs b/crates/erg_compiler/context/initialize/classes.rs
@@ -148,6 +148,19 @@ impl Context {
         float.register_py_builtin(OP_GE, fn1_met(Float, Float, Bool), Some(OP_GE), 0);
         float.register_py_builtin(OP_LT, fn1_met(Float, Float, Bool), Some(OP_LT), 0);
         float.register_py_builtin(OP_LE, fn1_met(Float, Float, Bool), Some(OP_LE), 0);
+        let t_nearly_eq = fn_met(
+            Float,
+            vec![kw(KW_OTHER, Float)],
+            None,
+            vec![kw(KW_EPSILON, Float)],
+            Bool,
+        );
+        float.register_builtin_erg_impl(
+            FUNC_NEARLY_EQ,
+            t_nearly_eq,
+            Immutable,
+            Visibility::BUILTIN_PUBLIC,
+        );
         let t_call = func1(Obj, Float);
         float.register_builtin_erg_impl(
             FUNDAMENTAL_CALL,

diff --git a/crates/erg_compiler/context/initialize/mod.rs b/crates/erg_compiler/context/initialize/mod.rs
@@ -410,6 +410,7 @@ const FUNC_HASATTR: &str = "hasattr";
 const FUNC_GETATTR: &str = "getattr";
 const FUNC_SETATTR: &str = "setattr";
 const FUNC_DELATTR: &str = "delattr";
+const FUNC_NEARLY_EQ: &str = "nearly_eq";
 
 const OP_EQ: &str = "__eq__";
 const OP_HASH: &str = "__hash__";
@@ -575,6 +576,7 @@ const KW_WHENCE: &str = "whence";
 const KW_CHARS: &str = "chars";
 const KW_OTHER: &str = "other";
 const KW_CONFLICT_RESOLVER: &str = "conflict_resolver";
+const KW_EPSILON: &str = "epsilon";
 
 pub fn builtins_path() -> PathBuf {
     erg_pystd_path().join("builtins.d.er")

diff --git a/crates/erg_compiler/lib/std/_erg_float.py b/crates/erg_compiler/lib/std/_erg_float.py
@@ -14,6 +14,9 @@ def try_new(i):  # -> Result[Nat]
     def mutate(self):
         return FloatMut(self)
 
+    def __abs__(self):
+        return Float(float.__abs__(self))
+
     def __add__(self, other):
         return then__(float.__add__(self, other), Float)
 
@@ -56,6 +59,8 @@ def __pos__(self):
     def __neg__(self):
         return then__(float.__neg__(self), Float)
 
+    def nearly_eq(self, other, epsilon=EPSILON):
+        return abs(self - other) < epsilon
 
 class FloatMut:  # inherits Float
     value: Float