Pick up japanese transaltionpr262-doc-followups

A bunch of minor README fixes, missing TOC, grammer cleanup

4 files changed, 4 insertions, 270 deletions

diff --git a/chapter20/README.ja.md b/chapter20/README.ja.md
index c33630e2..550844ca 100644
--- a/chapter20/README.ja.md
+++ b/chapter20/README.ja.md
@@ -7,6 +7,8 @@
 [前の章: 第19章](../chapter19/README.ja.md) |
 [次の章: 第21章](../chapter21/README.ja.md)
 
+文法は[第18章](../chapter18/docs/18-grammar.ja.md)から変わりません。
+
 ## 参考資料
 
 これは Briggs-Chaitin-Click 型の割り当て器であり、過去25年間にわたり大きな成功を収めてきた HotSpot の C2 割り当て器に非常によく似ています。
diff --git a/chapter20/README.md b/chapter20/README.md
index b4d4209f..e11dcff2 100644
--- a/chapter20/README.md
+++ b/chapter20/README.md
@@ -5,6 +5,8 @@ English | [日本語](README.ja.md)
 [Previous: Chapter 19](../chapter19/README.md) |
 [Next: Chapter 21](../chapter21/README.md)
 
+The grammar is unchanged from [Chapter 18](../chapter18/docs/18-grammar.md).
+
 ## Some Reading Material
 
 This is a Briggs-Chaitin-Click allocator, and is very similar to the one used
diff --git a/chapter20/docs/18-grammar.ja.md b/chapter20/docs/18-grammar.ja.md
deleted file mode 100644
index f0b12acb..00000000
--- a/chapter20/docs/18-grammar.ja.md
+++ /dev/null
@@ -1,138 +0,0 @@
-# 第20章の文法
-
-[English](18-grammar.md) | 日本語
-
-この文書は [原文](18-grammar.md) の日本語訳です。
-
-> 訳注: 原文の見出しは「Grammar for Chapter 16」です。この日本語版では、配置されている第20章に合わせた見出しにしています。
-
-[第20章に戻る](../README.ja.md)
-
-```antlrv4
-grammar SimpleLanguage;
-
-program : block EOF ;
-
-block : statement+ ;
-
-
-statement
-    : '{' block '}'
-    | returnStatement
-    | ifStatement
-    | whileStatement
-    | breakStatement
-    | continueStatement
-    | structDeclaration
-    | expressionStatement
-    ;
-
-
-returnStatement : 'return' expression ';' ;
-
-ifStatement : 'if' '(' expression ')' statement ('else' statement)? ;
-
-whileStatement : 'while' '(' expression ')' statement ;
-
-breakStatement : 'break' ';' ;
-
-continueStatement : 'continue' ';' ;
-
-
-structDeclaration : 'struct' IDENTIFIER '{' block '}'  ;
-
-expressionStatement
-    : type IDENTIFIER ';'
-    | type IDENTIFIER '=' expression ';'
-    |      IDENTIFIER '=' expression ';'
-    |                     expression
-    ;
-
-PRIMTYPE
-    : 'int'
-    | 'i8'
-    | 'i16'
-    | 'i32'
-    | 'i64'
-    | 'u8'
-    | 'u16'
-    | 'u32'
-    | 'flt'
-    | 'f32'
-    | 'f64'
-    | 'bool'
-    ;
-
-type
-    : PRIMTYPE
-    | typeName '?'?
-    | typeName nestedArray+
-    ;
-
-nestedArray : '?'?  '[]'* ;
-
-typeName : IDENTIFIER ;
-
-
-expression : bitWiseExpression ;
-
-bitWiseExpression
-    : comparisonExpression ( '&' | '|' | '^' ) comparisonExpression)*
-    ;
-    
-comparisonExpression
-    : shiftExpression (('==' | '!='| '>'| '<'| '>='| '<=') shiftExpression)*
-    ;
-
-shiftExpression
-    : additiveExpression ( '<<' | '>>>' | '>>' ) additiveExpression)*
-    ;
-    
-additiveExpression
-    : multiplicativeExpression (('+' | '-') multiplicativeExpression)*
-    ;
-
-multiplicativeExpression
-    : unaryExpression (('*' | '/') unaryExpression)*
-    ;
-
-unaryExpression
-    : ('-') unaryExpression
-    | '!' unaryExpression
-    | primaryExpression postAssign
-    ;
-
-primaryExpression
-    : INTEGER_LITERAL
-    | FLOAT_LITERAL
-    | '(' expression ')'
-    | 'true'
-    | 'false'
-    | 'null'
-    | newExpression
-    | IDENTIFIER
-    ;
-
-newExpression 
-    : 'new' IDENTIFIER [ '{' block '}' ]
-    | 'new' IDENTIFIER '[' expression ']'
-    ;
-
-postAssign : postFix [ '=' expression ] | [ '#' ];
-
-postFix
-    : '.' IDENTIFIER      postFix
-    | '[' expression ']'  postFix
-    ;
-
-
-IDENTIFIER : NON_DIGIT (NON_DIGIT | DIGIT)*  ;
-
-INTEGER_LITERAL
-    : [1-9]DIGIT*
-    | [0]
-    ;
-
-NON_DIGIT: [a-zA-Z_];
-DIGIT: [0-9];
-```
diff --git a/chapter20/docs/18-grammar.md b/chapter20/docs/18-grammar.md
deleted file mode 100644
index 51539d0b..00000000
--- a/chapter20/docs/18-grammar.md
+++ /dev/null
@@ -1,132 +0,0 @@
-# Grammar for Chapter 16
-
-English | [日本語](18-grammar.ja.md)
-
-```antlrv4
-grammar SimpleLanguage;
-
-program : block EOF ;
-
-block : statement+ ;
-
-
-statement
-    : '{' block '}'
-    | returnStatement
-    | ifStatement
-    | whileStatement
-    | breakStatement
-    | continueStatement
-    | structDeclaration
-    | expressionStatement
-    ;
-
-
-returnStatement : 'return' expression ';' ;
-
-ifStatement : 'if' '(' expression ')' statement ('else' statement)? ;
-
-whileStatement : 'while' '(' expression ')' statement ;
-
-breakStatement : 'break' ';' ;
-
-continueStatement : 'continue' ';' ;
-
-
-structDeclaration : 'struct' IDENTIFIER '{' block '}'  ;
-
-expressionStatement
-    : type IDENTIFIER ';'
-    | type IDENTIFIER '=' expression ';'
-    |      IDENTIFIER '=' expression ';'
-    |                     expression
-    ;
-
-PRIMTYPE
-    : 'int'
-    | 'i8'
-    | 'i16'
-    | 'i32'
-    | 'i64'
-    | 'u8'
-    | 'u16'
-    | 'u32'
-    | 'flt'
-    | 'f32'
-    | 'f64'
-    | 'bool'
-    ;
-
-type
-    : PRIMTYPE
-    | typeName '?'?
-    | typeName nestedArray+
-    ;
-
-nestedArray : '?'?  '[]'* ;
-
-typeName : IDENTIFIER ;
-
-
-expression : bitWiseExpression ;
-
-bitWiseExpression
-    : comparisonExpression ( '&' | '|' | '^' ) comparisonExpression)*
-    ;
-    
-comparisonExpression
-    : shiftExpression (('==' | '!='| '>'| '<'| '>='| '<=') shiftExpression)*
-    ;
-
-shiftExpression
-    : additiveExpression ( '<<' | '>>>' | '>>' ) additiveExpression)*
-    ;
-    
-additiveExpression
-    : multiplicativeExpression (('+' | '-') multiplicativeExpression)*
-    ;
-
-multiplicativeExpression
-    : unaryExpression (('*' | '/') unaryExpression)*
-    ;
-
-unaryExpression
-    : ('-') unaryExpression
-    | '!' unaryExpression
-    | primaryExpression postAssign
-    ;
-
-primaryExpression
-    : INTEGER_LITERAL
-    | FLOAT_LITERAL
-    | '(' expression ')'
-    | 'true'
-    | 'false'
-    | 'null'
-    | newExpression
-    | IDENTIFIER
-    ;
-
-newExpression 
-    : 'new' IDENTIFIER [ '{' block '}' ]
-    | 'new' IDENTIFIER '[' expression ']'
-    ;
-
-postAssign : postFix [ '=' expression ] | [ '#' ];
-
-postFix
-    : '.' IDENTIFIER      postFix
-    | '[' expression ']'  postFix
-    ;
-
-
-IDENTIFIER : NON_DIGIT (NON_DIGIT | DIGIT)*  ;
-
-INTEGER_LITERAL
-    : [1-9]DIGIT*
-    | [0]
-    ;
-
-NON_DIGIT: [a-zA-Z_];
-DIGIT: [0-9];
-```