class Result

Result of evaluating an expression.

Results form a tree that controls execution order and message passing between Ops.

index

members

• result:is_const()  – return whether this Result’s value is const.
• result:const([msg])  – assert value-constness and return the value.
• result:type()  – assert this result has a value, return its type.
• result:metatype()  – assert this result has a value, returns its metatype.
• result:make_ref()  – create a copy of this result with value-copy semantics.
• result:poll_io()  – poll all IOStream instances that are effecting this (sub)tree.
• result:tick()  – in depth-first order, tick all Ops which have dirty Inputs.
• result.value  – the Stream result
• result.op  – an Op
• result.children  – list of child Results from subexpressions
• result.side_inputs  – cached mapping of all Stream/Input pairs affecting this Result.

static functions

• Result(params)  – create a new Result.

details

members

• result:is_const()  – return whether this Result’s value is const.
• result:const([msg])  – assert value-constness and return the value.

  parameters:

  • msg (string): the error message to throw (optional)

  returns:

  1. (any)
• result:type()  – assert this result has a value, return its type.

  returns:

  1. (string)
• result:metatype()  – assert this result has a value, returns its metatype.

  returns:

  1. (string): "value" or "event"
• result:make_ref()  – create a copy of this result with value-copy semantics.
  the copy has the same @value and @side_inputs, but will not update anything on \tick.
• result:poll_io()  – poll all IOStream instances that are effecting this (sub)tree.
  should be called once per frame on the root, right before tick.
• result:tick()  – in depth-first order, tick all Ops which have dirty Inputs.
  short-circuits if there are no dirty Inputs in the entire subtree
• result.value  – the Stream result
  • value (optional Stream)
• result.op  – an Op
  • op (optional Op)
• result.children  – list of child Results from subexpressions
  • children ({} or {Result,...})
• result.side_inputs  – cached mapping of all Stream/Input pairs affecting this Result.
  This is the union of all childrens side_inputs and all Inputs from op that are not the value of any child.

  • side_inputs ({[Stream]=Input,...})

static functions

• Result(params)  – create a new Result.

  parameters:

  • params : table with optional keys op, value, children. default: {}