3.1 语法 ......................................................... 21
3.1.1 区分大小写 .................................. 21
3.1.2 标识符 .......................................... 21
3.1.3 注释 .............................................. 22
3.1.4 严格模式 ...................................... 22
3.1.5 语句 .............................................. 22
3.2 关键字与保留字 ...................................... 23
3.6.4 for 语句 ...................................... 74
3.6.5 for-in 语句 ................................ 75
3.6.6 for-of 语句 ................................ 76
3.6.7 标签语句 ...................................... 76
3.6.8 break 和 continue 语句 ........... 76
3.6.9 with 语句 .................................... 78
3.6.10 switch 语句 .............................. 78