Merge pull request #380 from notoria/char_type

Implementation of the predicate char_type for a subset

src/prolog/clause_types.rs

@@ -158,6 +158,7 @@ pub enum SystemClauseType {
     BindFromRegister,
     CallContinuation,
     CharCode,
+    CharType,
     CharsToNumber,
     ClearAttributeGoals,
     CloneAttributeGoals,
@@ -278,6 +279,7 @@ impl SystemClauseType {
             &SystemClauseType::BindFromRegister => clause_name!("$bind_from_register"),
             &SystemClauseType::CallContinuation => clause_name!("$call_continuation"),
             &SystemClauseType::CharCode => clause_name!("$char_code"),
+            &SystemClauseType::CharType => clause_name!("$char_type"),
             &SystemClauseType::CharsToNumber => clause_name!("$chars_to_number"),
             &SystemClauseType::CheckCutPoint => clause_name!("$check_cp"),
             &SystemClauseType::ClearAttributeGoals => clause_name!("$clear_attribute_goals"),
@@ -432,6 +434,7 @@ impl SystemClauseType {
             ("$assertz", 4) => Some(SystemClauseType::AssertDynamicPredicateToBack),
             ("$call_continuation", 1) => Some(SystemClauseType::CallContinuation),
             ("$char_code", 2) => Some(SystemClauseType::CharCode),
+            ("$char_type", 2) => Some(SystemClauseType::CharType),
             ("$chars_to_number", 2) => Some(SystemClauseType::CharsToNumber),
             ("$clear_attribute_goals", 0) => Some(SystemClauseType::ClearAttributeGoals),
             ("$clone_attribute_goals", 1) => Some(SystemClauseType::CloneAttributeGoals),

src/prolog/lib/charsio.pl

@@ -1,4 +1,4 @@
-:- module(charsio, [get_single_char/1,
+:- module(charsio, [char_type/2, get_single_char/1,
                     read_term_from_chars/2,
                     write_term_to_chars/3]).
 
@@ -57,6 +57,39 @@ extend_var_list_([V|Vs], N, VarList, NewVarList, VarType) :-
     ).
 
 
+char_type(Char, Type) :-
+    (   var(Char) -> throw(error(instantiation_error, char_type/2))
+    ;   atom_length(Char, 1) ->
+        (   ground(Type) -> '$char_type'(Char, Type)
+        ;   Type = symbolic_control, '$char_type'(Char, Type)
+        ;   Type = layout, '$char_type'(Char, Type)
+        ;   Type = symbolic_hexadecimal, Char = x
+        ;   Type = octal_digit, '$char_type'(Char, Type)
+        ;   Type = binary_digit, '$char_type'(Char, Type)
+        ;   Type = hexadecimal_digit, '$char_type'(Char, Type)
+        ;   Type = exponent, '$char_type'(Char, Type)
+        ;   Type = sign, '$char_type'(Char, Type)
+        ;   Type = upper, '$char_type'(Char, Type)
+        ;   Type = lower, '$char_type'(Char, Type)
+        ;   Type = graphic, '$char_type'(Char, Type)
+        ;   Type = alpha, '$char_type'(Char, Type)
+        ;   Type = decimal_digit, '$char_type'(Char, Type)
+        ;   Type = alnum, '$char_type'(Char, Type)
+        ;   Type = meta, '$char_type'(Char, Type)
+        ;   Type = solo, '$char_type'(Char, Type)
+        ;   Type = prolog, '$char_type'(Char, Type)
+        ;   Type = alphabetic, '$char_type'(Char, Type)
+        ;   Type = whitespace, '$char_type'(Char, Type)
+        ;   Type = control, '$char_type'(Char, Type)
+        ;   Type = numeric, '$char_type'(Char, Type)
+        ;   Type = ascii, '$char_type'(Char, Type)
+        ;   Type = ascii_punctuation, '$char_type'(Char, Type)
+        ;   Type = ascii_graphic, '$char_type'(Char, Type)
+        )
+    ;   throw(error(type_error(in_character, Char), char_type/2))
+    ).
+
+
 get_single_char(C) :-
     (  var(C) -> '$get_single_char'(C)
     ;  atom_length(C, 1) -> '$get_single_char'(C)

src/prolog/machine/system_calls.rs

@@ -1337,6 +1337,96 @@ impl MachineState {
                     }
                 };
             }
+            &SystemClauseType::CharType => {
+                let a1 = self.store(self.deref(self[temp_v!(1)]));
+                let a2 = self.store(self.deref(self[temp_v!(2)]));
+
+                let c = match a1 {
+                    Addr::Char(c) => c,
+                    Addr::Con(h) if self.heap.atom_at(h) => {
+                        if let HeapCellValue::Atom(name, _) = &self.heap[h] {
+                            name.as_str().chars().next().unwrap()
+                        }
+                        else {
+                            unreachable!()
+                        }
+                    }
+                    _ => unreachable!()
+                };
+                let chars = match a2 {
+                    Addr::Con(h) if self.heap.atom_at(h) => {
+                        if let HeapCellValue::Atom(name, _) = &self.heap[h] {
+                            name.as_str().to_string()
+                        }
+                        else {
+                            unreachable!()
+                        }
+                    }
+                    Addr::Char(c) => {
+                        c.to_string()
+                    }
+                    _ => unreachable!()
+                };
+                self.fail = true; // This predicate fails by default.
+                macro_rules! macro_check {
+                    ($id:ident, $name:tt) => {
+                if $id!(c) && chars == $name {
+                    self.fail = false;
+
+                    return return_from_clause!(self.last_call, self);
+                }
+                    }
+                }
+                macro_rules! method_check {
+                    ($id:ident, $name:tt) => {
+                if c.$id() && chars == $name {
+                    self.fail = false;
+
+                    return return_from_clause!(self.last_call, self);
+                }
+                    }
+                }
+                macro_check!(symbolic_control_char, "symbolic_control");
+                // macro_check!(space_char, "space");
+                macro_check!(layout_char, "layout");
+                macro_check!(symbolic_hexadecimal_char, "symbolic_hexadecimal");
+                macro_check!(octal_digit_char, "octal_digit");
+                macro_check!(binary_digit_char, "binary_digit");
+                macro_check!(hexadecimal_digit_char, "hexadecimal_digit");
+                macro_check!(exponent_char, "exponent");
+                macro_check!(sign_char, "sign");
+                // macro_check!(new_line_char, "new_line");
+                // macro_check!(comment_1_char, "comment_1");
+                // macro_check!(comment_2_char, "comment_2");
+                // macro_check!(capital_letter_char, "upper");
+                // macro_check!(small_letter_char, "lower");
+                // macro_check!(variable_indicator_char, "variable_indicator");
+                macro_check!(graphic_char, "graphic");
+                macro_check!(graphic_token_char, "graphic_token");
+                macro_check!(alpha_char, "alpha");
+                macro_check!(decimal_digit_char, "decimal_digit");
+                // macro_check!(decimal_point_char, "decimal_point");
+                // macro_check!(alpha_numeric_char, "alnum");
+                // macro_check!(cut_char, "cut");
+                // macro_check!(semicolon_char, "semicolon");
+                // macro_check!(backslash_char, "backslash");
+                // macro_check!(single_quote_char, "single_quote");
+                // macro_check!(double_quote_char, "double_quote");
+                // macro_check!(back_quote_char, "back_quote");
+                macro_check!(meta_char, "meta");
+                macro_check!(solo_char, "solo");
+                macro_check!(prolog_char, "prolog");
+                method_check!(is_alphabetic, "alphabetic");
+                method_check!(is_lowercase, "lower");
+                method_check!(is_uppercase, "upper");
+                method_check!(is_whitespace, "whitespace");
+                method_check!(is_alphanumeric, "alnum");
+                method_check!(is_control, "control");
+                method_check!(is_numeric, "numeric");
+                method_check!(is_ascii, "ascii");
+                method_check!(is_ascii_punctuation, "ascii_ponctuaction");
+                method_check!(is_ascii_graphic, "ascii_graphic");
+            }
             &SystemClauseType::CheckCutPoint => {
                 let addr = self.store(self.deref(self[temp_v!(1)]));