Let’s create a programming language! [SoundCloud HQ edition]

Transcript

1. Let’s create a
   programming

   language!
   DENIS DEFREYNE SOUNDCLOUD, BERLIN JUNE 7, 2016
   

   View Slide

2. 2
   dynamic vs. static
   

   View Slide

3. 3
   dynamic vs. static
   

   View Slide

4. 4
   compiler
   interpreter vs.
   

   View Slide

5. 5
   compiler
   interpreter vs.
   

   View Slide

6. but why?
   6
   

   View Slide

7. incremental
   7
   

   View Slide

8. Language 1
   8
   Numbers
   

   View Slide

9. %
   9
   cat stuff.cke
   4173
   5
   27
   2016
   

   View Slide

10. %
    10
    cat stuff.cke | ./clarke
    4173
    5
    27
    2016
    

    View Slide

11. 11
    module Grammar
    extend DParse::DSL
    DIGIT = char_in('0'..'9')
    PROGRAM = DIGIT
    end
    

    View Slide

12. 12
    res = Grammar::PROGRAM.apply($stdin.read)
    

    case res
    when DParse::Success
    handle_success(res)
    when DParse::Failure
    handle_failure(res)
    end
    

    View Slide

13. 13
    def handle_success(success)
    p success.data
    end
    

    View Slide

14. 14
    DIGIT = char_in('0'..'9')
    

    

    

    

    

    

    

    

    View Slide

15. 15
    DIGIT = …
    NUMBER = repeat1(DIGIT)
    

    

    

    

    

    View Slide

16. 16
    DIGIT = …
    NUMBER = repeat1(DIGIT)
    .capture
    

    

    

    

    

    View Slide

17. 17
    DIGIT = …
    NUMBER = repeat1(DIGIT)
    .capture
    .map { |d| d.to_i }
    

    

    

    

    

    View Slide

18. 18
    DIGIT = …
    NUMBER = …
    EXPRESSION = NUMBER
    

    

    

    

    

    

    View Slide

19. 19
    DIGIT = …
    NUMBER = …
    EXPRESSION = …
    EXPRESSIONS =
    intersperse(
    EXPRESSION,
    char("\n").ignore,
    ).compact
    

    View Slide

20. 20
    DIGIT = …
    NUMBER = …

    EXPRESSION = …
    EXPRESSIONS = …
    PROGRAM =
    seq(EXPRESSIONS, eof)
    .first

    

    

    View Slide

21. %
    21
    cat stuff.cke
    4173
    5
    27
    2016
    

    View Slide

22. %
    22
    cat stuff.cke | ./clarke
    [4173, 5, 27, 2016]
    

    View Slide

23. 23
    def handle_success(success)
    p success.data
    end
    

    View Slide

24. 24
    def handle_success(success)
    success.data.each do |expr|
    p eval_expr(expr)
    end
    end
    

    View Slide

25. 25
    def eval_expr(expr)
    expr
    end
    

    View Slide

26. %
    26
    cat stuff.cke | ./clarke
    4173
    5
    27
    2016
    

    View Slide

27. %
    27
    echo "aa" | ./clarke
    expected digit at line 1, column 1
    aa
    ↑
    

    View Slide

28. Language 2
    28
    Function calls
    

    View Slide

29. %
    29
    cat stuff.cke
    4173
    add(2, 5)
    

    View Slide

30. %
    30
    cat stuff.cke | ./clarke
    4173
    7
    

    View Slide

31. 31
    LETTER =
    char_in('a'..'z')
    FUNCTION_NAME =
    repeat1(LETTER).capture
    

    View Slide

32. 32
    FUNCTION_CALL =
    seq(
    FUNCTION_NAME,
    char('('),
    intersperse(
    lazy { EXPRESSION },
    char(','),
    ),
    char(')'),
    )
    

    View Slide

33. 33
    FUNCTION_CALL =
    seq(
    FUNCTION_NAME,
    char('('),
    intersperse(
    lazy { EXPRESSION },
    char(',').ignore,
    ).compact,
    char(')'),
    )
    

    View Slide

34. 34
    FUNCTION_CALL =
    seq(
    FUNCTION_NAME,
    char('(').ignore,
    intersperse(
    lazy { EXPRESSION },
    char(',').ignore,
    ).compact,
    char(')').ignore,
    ).compact
    

    View Slide

35. 35
    EXPRESSION =
    NUMBER
    

    View Slide

36. 36
    EXPRESSION =
    alt(NUMBER, FUNCTION_CALL)
    

    View Slide

37. %
    37
    cat stuff.cke
    4173
    add(2, 5)
    

    View Slide

38. %
    38
    cat stuff.cke | ./clarke
    4173
    ["add", [2, 5]]
    

    View Slide

39. 39
    FUNCTION_CALL =
    seq(
    FUNCTION_NAME,
    char('(').ignore,
    intersperse(
    lazy { EXPRESSION },
    char(',').ignore,
    ).compact,
    char(')').ignore,
    ).compact
    

    View Slide

40. 40
    def eval_expr(expr)
    expr
    end
    

    View Slide

41. 41
    def eval_expr(expr)
    case expr
    when Integer
    expr
    when Array
    eval_function_call(expr)
    end
    end
    

    View Slide

42. 42
    def eval_function_call(expr)
    case expr[0]
    when 'add'
    expr[1]
    .reduce(:+)
    when 'mul'
    …
    end
    end
    

    View Slide

43. 43
    def eval_function_call(expr)
    case expr[0]
    when 'add'
    expr[1]
    .map { |e| eval_expr(e) }
    .reduce(:+)
    when 'mul'
    …
    end
    end
    

    View Slide

44. %
    44
    cat stuff.cke
    4173
    add(2, add(1, 4))
    

    View Slide

45. %
    45
    cat stuff.cke | ./clarke
    4173
    7
    

    View Slide

46. Ugh, we forgot about whitespace.
    46
    

    View Slide

47. Cleanup 1
    47
    Abstract syntax
    

    View Slide

48. 48
    class IntNode < Struct.new(:value)
    end
    class FunCallNode < Struct.new(:name, :arguments)
    end
    

    View Slide

49. 49
    DIGIT = …
    NUMBER = repeat1(DIGIT)
    .capture
    .map { |d| d.to_i }
    

    

    

    

    

    View Slide

50. 50
    DIGIT = …
    NUMBER = repeat1(DIGIT)
    .capture
    .map { |d| IntNode.new(d.to_i) }
    

    

    

    

    

    View Slide

51. 51
    FUNCTION_CALL =
    seq(
    FUNCTION_NAME,
    char('(').ignore,
    intersperse(…),
    char(')').ignore,
    ).compact
    

    View Slide

52. 52
    FUNCTION_CALL =
    seq(
    FUNCTION_NAME,
    char('(').ignore,
    intersperse(…),
    char(')').ignore,
    ).compact.map do |data|
    FunCallNode.new(data[0], data[1])
    end
    

    View Slide

53. 53
    def eval_expr(expr)
    case expr
    when Integer
    expr
    when Array
    eval_function_call(expr)
    end
    end
    

    View Slide

54. 54
    def eval_expr(expr)
    case expr
    when IntNode
    expr.value
    when FunCallNode
    eval_function_call(expr)
    end
    end
    

    View Slide

55. 55
    def eval_function_call(expr)
    case expr[0]
    when 'add'
    expr[1]
    .map { |e| eval_expr(e) }
    .reduce(:+)
    when 'mul'
    …
    end
    end
    

    View Slide

56. 56
    def eval_function_call(expr)
    case expr.name
    when 'add'
    expr.args
    .map { |e| eval_expr(e) }
    .reduce(:+)
    when 'mul'
    …
    end
    end
    

    View Slide

57. Cleanup 2
    57
    Environment
    

    View Slide

58. 58
    $env = {}
    $env['add'] =
    FunDef.new(
    ['a', 'b'],
    ->(a, b) { a + b },
    )
    

    View Slide

59. 59
    class FunDef < Struct.new(:args, :body)
    end
    

    View Slide

60. 60
    def eval_function_call(expr)
    case expr.name
    when 'add'
    expr.args
    .map { |e| eval_expr(e) }
    .reduce(:+)
    when 'mul'
    …
    end
    end
    

    View Slide

61. 61
    def eval_function_call(expr)
    fun = $env[expr.name]
    values = expr.args.map { |e| eval_expr(e) }
    fun.body.call(*values)
    end
    

    View Slide

62. … with error handling, of course.
    62
    

    View Slide

63. Language 3
    63
    Variables
    

    View Slide

64. %
    64
    cat stuff.cke
    4173
    add(2,amount)
    

    View Slide

65. %
    65
    cat stuff.cke | ./clarke
    4173
    7
    

    View Slide

66. 66
    class VarNode < Struct.new(:name)
    end
    

    View Slide

67. 67
    VARIABLE_NAME =
    repeat1(LETTER).capture
    

    View Slide

68. 68
    VARIABLE_REFERENCE =
    VARIABLE_NAME
    .map { |d| VarNode.new(d) }
    

    View Slide

69. 69
    EXPRESSION =
    alt(

    NUMBER,

    FUNCTION_CALL,

    )

    

    View Slide

70. 70
    EXPRESSION =
    alt(
    NUMBER,
    FUNCTION_CALL,
    VARIABLE_REFERENCE,
    )
    

    View Slide

71. 71
    def eval_expr(expr)
    case expr
    when IntNode
    expr.value
    when FunCallNode
    eval_function_call(expr)
    end
    end

    

    

    View Slide

72. 72
    def eval_expr(expr)
    case expr
    when IntNode
    expr.value
    when FunCallNode
    eval_function_call(expr)
    when VarNode
    eval_var(expr)
    end
    end
    

    View Slide

73. 73
    def eval_var(expr)
    $env[expr.name]
    end
    

    View Slide

74. 74
    $env['amount'] = 5
    

    View Slide

75. Language 3.1
    75
    Variable assignment
    

    View Slide

76. %
    76
    cat stuff.cke
    4173
    amount=5
    add(2,amount)
    

    View Slide

77. %
    77
    cat stuff.cke | ./clarke
    4173
    7
    

    View Slide

78. 78
    class AssignNode < Struct.new(:name, :rhs)
    end
    

    View Slide

79. 79
    ASSIGNMENT =
    seq(
    VARIABLE_NAME,
    char('='),
    lazy { EXPRESSION },
    )
    

    View Slide

80. 80
    ASSIGNMENT =
    seq(
    VARIABLE_NAME,
    char('=').ignore,
    lazy { EXPRESSION },
    ).compact
    

    View Slide

81. 81
    ASSIGNMENT =
    seq(
    VARIABLE_NAME,
    char('=').ignore,
    lazy { EXPRESSION },
    ).compact.map do |data|
    AssignNode.new(data[0], data[1])
    end
    

    View Slide

82. 82
    EXPRESSION =
    alt(
    NUMBER,
    FUNCTION_CALL,
    VARIABLE_REFERENCE,
    )

    

    View Slide

83. 83
    EXPRESSION =
    alt(
    NUMBER,
    FUNCTION_CALL,
    VARIABLE_REFERENCE,
    ASSIGNMENT,
    )
    

    View Slide

84. 84
    def eval_expr(expr)
    case expr
    when …
    …
    when AssignNode
    eval_assign(expr)
    end
    end
    

    View Slide

85. 85
    def eval_assign(expr)
    $env[expr.name] = eval_expr(expr.rhs)
    end
    

    View Slide

86. Cleanup 3
    86
    Print function
    

    View Slide

87. 87
    def handle_success(success)
    success.data.each do |expr|
    p eval_expr(expr)
    end
    end
    

    View Slide

88. 88
    def handle_success(success)
    success.data.each do |expr|
    eval_expr(expr)
    end
    end
    

    View Slide

89. 89
    $env['print'] =
    FunDef.new(
    ['a'],
    ->(a) { p a },
    )
    

    View Slide

90. %
    90
    cat stuff.cke
    4173
    amount=5
    print(add(2,amount))
    

    View Slide

91. %
    91
    cat stuff.cke | ./clarke
    7
    

    View Slide

92. Cleanup 4
    92
    Immutable env
    

    View Slide

93. 93
    def eval_expr(expr)
    case expr
    when …
    …
    when AssignNode
    eval_assign(expr)
    end
    end
    

    View Slide

94. 94
    def eval_expr(expr, env)
    case expr
    when …
    …
    when AssignNode
    eval_assign(expr, env)
    end
    end
    

    View Slide

95. 95
    def eval_assign(expr)
    $env[expr.name] = eval_expr(expr.rhs)
    end

    

    

    View Slide

96. 96
    def eval_assign(expr, env)
    $env[expr.name] = eval_expr(expr.rhs)
    end

    

    

    View Slide

97. 97
    def eval_assign(expr, env)
    val = eval_expr(expr.rhs)
    new_env = env.merge(expr.name => val)
    ValAndEnv.new(val, new_env)
    end
    

    View Slide

98. 98
    class ValAndEnv < Struct.new(:val, :env)
    end
    

    View Slide

99. 99
    def handle_success(success)
    success.data.each do |expr|
    eval_expr(expr)
    end
    end
    

    View Slide

100. 100
     def handle_success(success)
     init = ValAndEv.new(0, INITIAL_ENV)
     

     

     

     

     View Slide

101. 101
     def handle_success(success)
     init = ValAndEv.new(0, INITIAL_ENV)
     success.data.reduce(init) do |result, e|
     eval_expr(e, result.env)
     end
     end
     

     View Slide

102. 102
     INITIAL_ENV = {
     'add' => FunDef.new(
     ['a', 'b'],
     ->(a, b) { a + b },
     )
     }
     

     View Slide

103. Language 4
     103
     Scopes
     

     View Slide

104. %
     104
     cat stuff.cke
     4173
     amount = {
     a = 2
     b = 3
     add(a, b)
     }
     print(add(2, amount))
     

     View Slide

105. %
     105
     cat stuff.cke | ./clarke
     7
     

     View Slide

106. 106
     class ScopeNode < Struct.new(:exprs)
     end
     

     View Slide

107. 107
     SCOPE =
     seq(
     char('{'),
     repeat1(lazy { EXPRESSION }),
     char('}'),
     )
     

     View Slide

108. 108
     SCOPE =
     seq(
     char('{').ignore,
     repeat1(lazy { EXPRESSION }),
     char('}').ignore,
     ).compact
     

     View Slide

109. 109
     SCOPE =
     seq(
     char('{').ignore,
     repeat1(lazy { EXPRESSION }),
     char('}').ignore,
     ).compact.map do |data|
     ScopeNode.new(data[0])
     end
     

     View Slide

110. 110
     EXPRESSION =
     alt(
     NUMBER,
     FUNCTION_CALL,
     VARIABLE_REFERENCE,
     ASSIGNMENT,
     )

     

     View Slide

111. 111
     EXPRESSION =
     alt(
     NUMBER,
     FUNCTION_CALL,
     VARIABLE_REFERENCE,
     ASSIGNMENT,
     SCOPE,
     )
     

     View Slide

112. 112
     def eval_expr(expr, env)
     case expr
     when …
     …
     when ScopeNode
     eval_scope(expr, env)
     end
     end
     

     View Slide

113. 113
     def eval_scope(expr, env)
     init = ValAndEnv.new(0, env)
     result =
     expr.exprs.reduce(init) do |result, e|
     eval_expr(e, result.env)
     end
     ValAndEnv.new(result.val, env)
     end
     

     View Slide

114. 114
     def eval_scope(expr, env)
     init = ValAndEnv.new(0, env)
     result =
     expr.exprs.reduce(init) do |result, e|
     eval_expr(e, result.env)
     end
     ValAndEnv.new(result.val, env)
     end
     

     View Slide

115. %
     115
     cat stuff.cke
     4173
     amount = {
     a = 2
     b = 3
     add(a, b)
     }
     print(add(2, amount))
     

     View Slide

116. Language 5
     116
     Conditionals
     

     View Slide

117. %
     117
     cat stuff.cke
     if (0) {
     print(100)
     } else {
     print(200)
     }
     

     View Slide

118. %
     118
     cat stuff.cke | ./clarke
     200
     

     View Slide

119. SKIP
     119
     

     View Slide

120. Language 6
     120
     Function definitions
     

     View Slide

121. %
     121
     cat stuff.cke
     fun multiply(a, b) {
     if (b) {
     add(a, multiply(a, sub(b, 1)))
     } else {
     0
     }
     }
     print(multiply(3, 5))
     

     View Slide

122. 122
     class FunDefNode < Struct.new(
     :name, :argument_names, :body)
     end
     

     View Slide

123. 123
     FUNCTION_DEF =
     seq(
     string('fun'),
     FUNCTION_NAME,
     char('('),
     intersperse(
     VARIABLE_NAME,
     char(','),
     ),
     char(')'),
     SCOPE,
     )

     

     

     View Slide

124. 124
     FUNCTION_DEF =
     seq(
     string('fun').ignore,
     FUNCTION_NAME,
     char('(').ignore,
     intersperse(
     VARIABLE_NAME,
     char(',').ignore,
     ).compact,
     char(')').ignore,
     SCOPE,
     ).compact

     

     

     View Slide

125. 125
     FUNCTION_DEF =
     seq(
     string('fun').ignore,
     FUNCTION_NAME,
     char('(').ignore,
     intersperse(
     VARIABLE_NAME,
     char(',').ignore,
     ).compact,
     char(')').ignore,
     SCOPE,
     ).compact.map do |data|
     FunDefNode.new(data[0], data[1], data[2])
     end
     

     View Slide

126. 126
     class FunDef < Struct.new(:argument_names, :body)
     end
     

     View Slide

127. View Slide

128. 127
     def eval_function_def(expr, env)
     

     View Slide

129. 127
     def eval_function_def(expr, env)
     fun_def = FunDef.new(

     expr.argument_names, expr.body)

     

     View Slide

130. 127
     def eval_function_def(expr, env)
     fun_def = FunDef.new(

     expr.argument_names, expr.body)

     ValAndEnv.new(

     fun_def,

     env.merge(expr.name => fun_def),

     )

     end
     

     View Slide

131. 128
     def eval_function_call(expr, env)
     fun = env[expr.name]
     values = expr.args.map { |e| eval_expr(e) }
     

     

     

     

     fun.body.call(*values)
     

     View Slide

132. 129
     def eval_function_call(expr, env)
     fun = env[expr.name]
     values = expr.args.map { |e| eval_expr(e) }
     case fun.body
     when Proc
     when Scope
     …
     fun.body.call(*values)
     

     View Slide

133. 129
     def eval_function_call(expr, env)
     fun = env[expr.name]
     values = expr.args.map { |e| eval_expr(e) }
     case fun.body
     when Proc
     when Scope
     …
     fun.body.call(*values)
     

     View Slide

134. View Slide

135. 130
     when Scope

     new_env = env.merge(

     Hash[fun.argument_names.zip(values)])

     

     View Slide

136. 130
     when Scope

     new_env = env.merge(

     Hash[fun.argument_names.zip(values)])

     eval_scope(fun.body, new_env)

     end
     

     View Slide

137. %
     131
     cat stuff.cke
     fun multiply(a, b) {
     if (b) {
     add(a, multiply(a, sub(b, 1)))
     } else {
     0
     }
     }
     print(multiply(3, 5))
     

     View Slide

138. Language 7
     132
     Operators
     

     View Slide

139. %
     133
     cat stuff.cke
     fun multiply(a, b) {
     if (b) {
     a + multiply(a, b - 1)
     } else {
     0
     }
     }
     print(multiply(3, 5))
     

     View Slide

140. 134
     10 - 2 - 5 * 2 + 2 ^ 3 ^ 4
     

     View Slide

141. 135
     1. Precedence
     

     View Slide

142. 136
     4 + 5 * 2_
     

     View Slide

143. 137
     4 + (5 * 2)
     

     View Slide

144. 138
     (4 + 5) * 2 _
     

     View Slide

145. 138
     (4 + 5) * 2 _
     WRONG!
     

     View Slide

146. 139
     2. Associativity
     

     View Slide

147. 140
     2 ^ 3 ^ 4_
     

     View Slide

148. 141
     2 ^ (3 ^ 4)
     

     View Slide

149. 142
     (2 ^ 3) ^ 4__
     

     View Slide

150. 142
     (2 ^ 3) ^ 4__
     WRONG!
     

     View Slide

151. 143
     Shunting-yard algorithm
     (en.wikipedia.org/wiki/Shunting-yard_algorithm)
     

     View Slide

152. View Slide

153. 144
     input: infix notation e.g. a + b * c
     

     View Slide

154. 144
     input: infix notation e.g. a + b * c
     precedences e.g. a + b * c
     

     View Slide

155. 144
     input: infix notation e.g. a + b * c
     precedences e.g. a + b * c
     associativities e.g. a + b * c
     

     View Slide

156. 144
     input: infix notation e.g. a + b * c
     precedences e.g. a + b * c
     associativities e.g. a + b * c
     

     output: postfix notation e.g. a b c * +
     

     View Slide

157. 145
     tokens =
     "10 - 2 - 5 * 2 + 2 ^ 3 ^ 4"
     .split(" ")
     

     

     

     

     

     

     

     

     View Slide

158. 146
     tokens =
     "10 - 2 - 5 * 2 + 2 ^ 3 ^ 4"
     .split(" ")
     res = shunting_yard(
     tokens,
     PRECEDENCES,
     ASSOCIATIVITIES,
     )
     

     View Slide

159. 147
     tokens =
     "10 - 2 - 5 * 2 + 2 ^ 3 ^ 4"
     .split(" ")
     res = shunting_yard(
     tokens,
     PRECEDENCES,
     ASSOCIATIVITIES,
     )
     puts res.join(' ')
     

     View Slide

160. 148
     PRECEDENCES = {
     '^' => 3,
     '*' => 2,
     '/' => 2,
     '+' => 1,
     '-' => 1,
     }
     

     View Slide

161. 149
     ASSOCIATIVITIES = {
     '^' => :right,
     '*' => :left,
     '/' => :left,
     '+' => :left,
     '-' => :left,
     }
     

     View Slide

162. 150
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     

     View Slide

163. 151
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     10
     

     View Slide

164. 152
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     2
     10
     

     View Slide

165. 153
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     8
     

     View Slide

166. 154
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     5
     8
     

     View Slide

167. 155
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     2
     5
     8
     

     View Slide

168. 156
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     10
     8
     

     View Slide

169. 157
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     -2
     

     View Slide

170. 158
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     2
     -2
     

     View Slide

171. 159
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     3
     2
     -2
     

     View Slide

172. 160
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     4
     3
     2
     -2
     

     View Slide

173. 161
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     81
     2
     -2
     

     View Slide

174. 162
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     241785163
     -2
     

     View Slide

175. 163
     10 2 - 5 2 * - 2 3 4 ^ ^ +
     241785163
     

     View Slide

176. 164
     OPERATOR =
     alt(
     char('^'),
     char('*'),
     char('/'),
     char('+'),
     char('-'),
     )
     

     View Slide

177. 165
     BIN_OP_EXPRESSION =
     intersperse(
     OPERAND,
     OPERATOR,
     )
     

     View Slide

178. 166
     postfix_tokens = shunting_yard(

     expr.tokens, PRECEDENCES, ASSOCIATIVITIES)
     stack = []
     postfix_tokens.each do |e|
     if e.is_a?(Clarke::AST::Op)
     values = [stack.pop, stack.pop]
     stack.push(eval_op(e, values))
     else
     stack.push(e)
     end
     end
     

     View Slide

179. 167
     def eval_op(e, values)
     case e.name
     when '^'
     values.reduce(:**)
     when '+'
     values.reduce(:+)
     when …
     end
     end
     

     View Slide

180. %
     168
     cat stuff.cke
     fun multiply(a, b) {
     if (b) {
     a + multiply(a, b - 1)
     } else {
     0
     }
     }
     print(multiply(3, 5))
     

     View Slide

181. etc.
     

     View Slide

182. Types! Loops! Closures! Objects!

     Classes! Inheritance! Tuples! Records!
     Typechecking! Multimethods!
     Enumerations! Proper lexical scoping!
     Pattern matching! Currying! Modules!
     170
     

     View Slide

183. View Slide

184. 171
     L1 Numbers
     

     View Slide

185. 171
     L1 Numbers
     L2 Function calls
     

     View Slide

186. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     

     View Slide

187. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     

     View Slide

188. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     L3 Variables
     

     View Slide

189. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     L3 Variables
     C3 Print function
     

     View Slide

190. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     L3 Variables
     C3 Print function
     C4 Immutable environment
     

     View Slide

191. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     L3 Variables
     C3 Print function
     C4 Immutable environment
     L4 Scopes
     

     View Slide

192. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     L3 Variables
     C3 Print function
     C4 Immutable environment
     L4 Scopes
     L5 Conditionals
     

     View Slide

193. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     L3 Variables
     C3 Print function
     C4 Immutable environment
     L4 Scopes
     L5 Conditionals
     L6 Function definitions
     

     View Slide

194. 171
     L1 Numbers
     L2 Function calls
     C1 Abstract syntax
     C2 Environment
     L3 Variables
     C3 Print function
     C4 Immutable environment
     L4 Scopes
     L5 Conditionals
     L6 Function definitions
     L7 Operators
     

     View Slide

195. 172
     github.com/ddfreyne/clarke
     

     View Slide

196. 172
     github.com/ddfreyne/clarke
     SOON
     

     View Slide

197. 173
     Ready to
     interpret
     your questions.
     DENIS@SOUNDCLOUD.COM @DENIS
     

     View Slide