Documentation

Overview

    Package vars implement lucicfg.var() support.

    See lucicfg.var() doc for more info.

    Index

    Constants

    This section is empty.

    Variables

    This section is empty.

    Functions

    This section is empty.

    Types

    type ID

    type ID int

      ID is an opaque starlark value that represents a lucifg.var() variable.

      It is just a unique identifier for this particular variable, used as a key in a map with variables values.

      func (ID) Freeze

      func (v ID) Freeze()

      func (ID) Hash

      func (v ID) Hash() (uint32, error)

      func (ID) String

      func (v ID) String() string

      func (ID) Truth

      func (v ID) Truth() starlark.Bool

      func (ID) Type

      func (v ID) Type() string

      type Vars

      type Vars struct {
      	// DeclaredExposeAsAliases is a set of all `exposeAs` passed to Declare.
      	DeclaredExposeAsAliases stringset.Set
      	// contains filtered or unexported fields
      }

        Vars holds definitions and current state of lucicfg.var() variables.

        It exposes OpenScope/CloseScope that should be connected to PreExec/PostExec interpreter hooks. They "open" and "close" scopes for variables: all changes made to vars state within a scope (i.e. within single exec-ed module) are discarded when the scope is closed.

        func (*Vars) ClearValues

        func (v *Vars) ClearValues()

          ClearValues resets values of all variables, in all scopes.

          Should be used only from tests that want a clean slate.

          func (*Vars) CloseScope

          func (v *Vars) CloseScope(th *starlark.Thread)

            CloseScope discards changes made to variables since the matching OpenScope.

            func (*Vars) Declare

            func (v *Vars) Declare(th *starlark.Thread, exposeAs string, presetVal starlark.Value) (ID, error)

              Declare allocates a new variable, setting it right away to 'presetVal' value if 'exposeAs' not empty.

              Variables that were pre-set during declaration are essentially immutable throughout lifetime of the interpreter.

              Returns an error if a variable with the same `exposeAs` name has already been exposed.

              func (*Vars) Get

              func (v *Vars) Get(th *starlark.Thread, id ID, def starlark.Value) (starlark.Value, error)

                Get returns the value of a variable, auto-initializing it to 'def' if it was unset before.

                Variable can be assigned or read only from threads that perform 'exec' calls, NOT when loading library modules via 'load' (the library modules must not have side effects or depend on a transient state in vars), or executing callbacks (callbacks do not have enough context to safely use vars).

                func (*Vars) OpenScope

                func (v *Vars) OpenScope(th *starlark.Thread)

                  OpenScope opens a new scope for variables.

                  All changes to variables' values made within this scope are discarded when it is closed.

                  func (*Vars) Set

                  func (v *Vars) Set(th *starlark.Thread, id ID, value starlark.Value) error

                    Set sets the value of a variable within the current scope iff the variable was unset before (in the current or any parent scopes).

                    Variable can be assigned or read only from threads that perform 'exec' calls, NOT when loading library modules via 'load' (the library modules must not have side effects or depend on a transient state in vars), or executing callbacks (callbacks do not have enough context to safely use vars).

                    Freezes the value as a side effect.

                    Source Files