Establishing generic parselets and functions (#105)

CHANGELOG.md

@@ -4,6 +4,18 @@
 
 Current main branch.
 
+- Implementation of generic parselets
+  - Syntax changes
+  - Handle parselet instances
+  - Handle generic values in intermediate structures
+  - System-defined parselets in prelude
+    - `Repeat<P, min: 1, max: void>`
+      - Implement `Pos<P>`, `Opt<P>`, `Kle<P>`
+      - Compile `P+` into `Pos<P>`, `P?` into `Opt<P>`, `P*` into `Kle<P>`
+    - `List<P, Sep: (',' _), empty: true>`
+    - `Peek<P>`, replaced `peek P` by `Peek<P>`
+    - `Not<P>`, replaced `not P` by `Not<P>`
+    - `Expect<P> msg=void`, replaced `expect P` by `Expect<P>`
 - v0.6.4:
   - Main parselet operates on multiple inputs (Readers) now
   - Restructuring parts of VM, `Runtime` renamed into `Thread`

ROADMAP.md

@@ -5,7 +5,8 @@ This document describes upcoming changes to achieve with a specific version.
 ## 0.7
 
 - [x] Implement iterators and `for...in`-syntax (#101)
-- [ ] Implement generic parselets (#10, #105)
+- [x] Implement generic parselets (#10, #105)
+- [ ] Implement embedded parselets (#120)
 - [ ] New list syntax `[...]`, redefining sequence/`dict` syntax (#100)
   - The character-class token syntax was replaced by a `Char`-builtin
   - List definition `list = []`

build/Makefile

@@ -6,6 +6,7 @@ all:
 	@echo ""
 	@echo "  make builtins    update src/_builtins.rs from src/"
 	@echo "  make parser      update src/compiler/parse.rs from src/compiler/tokay.tok"
+	@echo "  make prelude     update src/compiler/prelude.rs from src/prelude.tok"
 	@echo ""
 
 # builtins --------------------------------------------------------------------
@@ -36,3 +37,17 @@ show-parser:
 
 reset-parser:
 	git checkout $(PARSER)
+
+# prelude ----------------------------------------------------------------------
+PRELUDE=../src/compiler/prelude.rs
+
+prelude: $(PRELUDE)
+
+$(PRELUDE): .FORCE
+	$(ETARENEG) $@ >$@.1 && mv $@.1 $@
+
+show-prelude:
+	$(ETARENEG) $(PRELUDE) 2>/dev/null
+
+reset-prelude:
+	git checkout $(PRELUDE)

examples/minicalc.tok

@@ -0,0 +1,11 @@
+
+Main : @{
+    Expect<Expr>    print("= " + $1)
+}
+
+Expr : @{
+    Expr '+' Int    $1 + $3
+    Int
+}
+
+Main

src/_builtins.rs

@@ -6,7 +6,7 @@
 use crate::builtin::Builtin;
 
 /*GENERATE cargo run -- _builtins.tok -- `find . -name "*.rs"` */
-pub static BUILTINS: [Builtin; 63] = [
+pub static BUILTINS: [Builtin; 64] = [
     Builtin {
         name: "Float",
         func: crate::value::token::tokay_token_float,
@@ -87,6 +87,10 @@ pub static BUILTINS: [Builtin; 63] = [
         name: "dict_set_item",
         func: crate::value::dict::Dict::tokay_method_dict_set_item,
     },
+    Builtin {
+        name: "eof",
+        func: crate::builtin::tokay_function_eof,
+    },
     Builtin {
         name: "error",
         func: crate::error::tokay_function_error,

src/builtin/mod.rs

@@ -182,7 +182,9 @@ tokay_function!("type : @value", value!(value.name()).into());
 tokay_function!("debug : @level", {
     if let Ok(level) = level.to_usize() {
         if level < u8::MAX as usize {
-            context.unwrap().thread.debug = level as u8;
+            let context = context.unwrap();
+            context.debug = level as u8;
+            //context.thread.debug = level as u8;
             return Ok(Accept::Next);
         }
     }
@@ -210,3 +212,7 @@ tokay_function!("offset : @", {
     ])
     .into()
 });
+
+tokay_function!("eof : @", {
+    value!(context.unwrap().thread.reader.eof()).into()
+});