class SyntaxTree::YARV::BranchNil

### Summary

‘branchnil` has one argument: the jump index. It pops one value off the stack: the jump condition.

If the value popped off the stack is nil, ‘branchnil` jumps to the jump index and continues executing there.

### Usage

~~~ruby x = nil if x&.to_s

puts "hi"

end ~~~

label[R]

new(label) click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 239
def initialize(label)
  @label = label
end

==(other) click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 255
def ==(other)
  other.is_a?(BranchNil) && other.label == label
end

branch_targets() click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 271
def branch_targets
  [label]
end

call(vm) click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 267
def call(vm)
  vm.jump(label) if vm.pop.nil?
end

deconstruct_keys(_keys) click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 251
def deconstruct_keys(_keys)
  { label: label }
end

disasm(fmt) click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 243
def disasm(fmt)
  fmt.instruction("branchnil", [fmt.label(label)])
end

falls_through?() click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 275
def falls_through?
  true
end

length() click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 259
def length
  2
end

pops() click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 263
def pops
  1
end

to_a(_iseq) click to toggle source

# File lib/syntax_tree/yarv/instructions.rb, line 247
def to_a(_iseq)
  [:branchnil, label.name]
end