lang: core: Add list and map packages
Put the common functionality for those types in there.
This commit is contained in:
James Shubin
@@ -44,6 +44,8 @@ import (
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_ "github.com/purpleidea/mgmt/lang/core/example/nested"
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_ "github.com/purpleidea/mgmt/lang/core/fmt"
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_ "github.com/purpleidea/mgmt/lang/core/iter"
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_ "github.com/purpleidea/mgmt/lang/core/list"
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_ "github.com/purpleidea/mgmt/lang/core/map"
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_ "github.com/purpleidea/mgmt/lang/core/math"
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_ "github.com/purpleidea/mgmt/lang/core/net"
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_ "github.com/purpleidea/mgmt/lang/core/os"
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35
lang/core/list/list.go
Normal file
35
lang/core/list/list.go
Normal file
@@ -0,0 +1,35 @@
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// Mgmt
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// Copyright (C) 2013-2024+ James Shubin and the project contributors
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// Written by James Shubin <james@shubin.ca> and the project contributors
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//
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// This program is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program. If not, see <https://www.gnu.org/licenses/>.
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//
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// Additional permission under GNU GPL version 3 section 7
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//
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// If you modify this program, or any covered work, by linking or combining it
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// with embedded mcl code and modules (and that the embedded mcl code and
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// modules which link with this program, contain a copy of their source code in
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// the authoritative form) containing parts covered by the terms of any other
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// license, the licensors of this program grant you additional permission to
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// convey the resulting work. Furthermore, the licensors of this program grant
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// the original author, James Shubin, additional permission to update this
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// additional permission if he deems it necessary to achieve the goals of this
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// additional permission.
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package corelist
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const (
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// ModuleName is the prefix given to all the functions in this module.
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ModuleName = "list"
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)
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306
lang/core/list/list_lookup_func.go
Normal file
306
lang/core/list/list_lookup_func.go
Normal file
@@ -0,0 +1,306 @@
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// Mgmt
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// Copyright (C) 2013-2024+ James Shubin and the project contributors
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// Written by James Shubin <james@shubin.ca> and the project contributors
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//
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// This program is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program. If not, see <https://www.gnu.org/licenses/>.
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//
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// Additional permission under GNU GPL version 3 section 7
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//
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// If you modify this program, or any covered work, by linking or combining it
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// with embedded mcl code and modules (and that the embedded mcl code and
|
||||
// modules which link with this program, contain a copy of their source code in
|
||||
// the authoritative form) containing parts covered by the terms of any other
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// license, the licensors of this program grant you additional permission to
|
||||
// convey the resulting work. Furthermore, the licensors of this program grant
|
||||
// the original author, James Shubin, additional permission to update this
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// additional permission if he deems it necessary to achieve the goals of this
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// additional permission.
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package corelist
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import (
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"context"
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"fmt"
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"math"
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"github.com/purpleidea/mgmt/lang/funcs"
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"github.com/purpleidea/mgmt/lang/interfaces"
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"github.com/purpleidea/mgmt/lang/types"
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"github.com/purpleidea/mgmt/util/errwrap"
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)
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const (
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// ListLookupFuncName is the name this function is registered as.
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ListLookupFuncName = "lookup" // list.lookup
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// arg names...
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listLookupArgNameList = "list"
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listLookupArgNameIndex = "index"
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listLookupArgNameDefault = "default"
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)
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func init() {
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funcs.ModuleRegister(ModuleName, ListLookupFuncName, func() interfaces.Func { return &ListLookupFunc{} }) // must register the func and name
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}
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var _ interfaces.BuildableFunc = &ListLookupFunc{} // ensure it meets this expectation
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// ListLookupFunc is a list index lookup function. It can take either two or
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// three arguments. The first argument is the list to lookup a value in. The
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// second is the integer index. If you specify a third argument, then this value
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// will be returned if the list index is not present. If the third argument is
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// omitted, then this function errors if the list index is not present. Passing
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// a negative index will always result in an error.
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type ListLookupFunc struct {
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Type *types.Type // Kind == List, that is used as the list we lookup in
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hasDefault *bool // does this function take a third arg?
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init *interfaces.Init
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last types.Value // last value received to use for diff
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result types.Value // last calculated output
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}
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// String returns a simple name for this function. This is needed so this struct
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// can satisfy the pgraph.Vertex interface.
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func (obj *ListLookupFunc) String() string {
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return ListLookupFuncName
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}
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// ArgGen returns the Nth arg name for this function.
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func (obj *ListLookupFunc) ArgGen(index int) (string, error) {
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seq := []string{listLookupArgNameList, listLookupArgNameIndex, listLookupArgNameDefault}
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if l := len(seq); index >= l {
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return "", fmt.Errorf("index %d exceeds arg length of %d", index, l)
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}
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return seq[index], nil
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}
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// helper
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func (obj *ListLookupFunc) sig() *types.Type {
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// func(list []?1, index int) ?1
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// OR
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// func(list []?1, index int, default ?1) ?1
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if obj.hasDefault == nil { // not yet known
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return nil
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}
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v := "?1"
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if obj.Type != nil { // don't panic if called speculatively
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v = obj.Type.Val.String()
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}
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if *obj.hasDefault {
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return types.NewType(fmt.Sprintf(
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"func(%s []%s, %s int, %s %s) %s",
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listLookupArgNameList, v,
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listLookupArgNameIndex,
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listLookupArgNameDefault, v,
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v,
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))
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}
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return types.NewType(fmt.Sprintf(
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"func(%s []%s, %s int) %s",
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listLookupArgNameList, v,
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listLookupArgNameIndex,
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v,
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))
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}
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// FuncInfer takes partial type and value information from the call site of this
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// function so that it can build an appropriate type signature for it. The type
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// signature may include unification variables.
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func (obj *ListLookupFunc) FuncInfer(partialType *types.Type, partialValues []types.Value) (*types.Type, []*interfaces.UnificationInvariant, error) {
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if l := len(partialValues); l != 2 && l != 3 {
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return nil, nil, fmt.Errorf("function must have either 2 or 3 args")
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}
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b := false
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//if len(partialValues) == 2 {
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// b = false
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//}
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if len(partialValues) == 3 {
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b = true
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}
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obj.hasDefault = &b // store for later
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return obj.sig(), []*interfaces.UnificationInvariant{}, nil
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}
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// Build is run to turn the polymorphic, undetermined function, into the
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// specific statically typed version. It is usually run after Unify completes,
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// and must be run before Info() and any of the other Func interface methods are
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// used. This function is idempotent, as long as the arg isn't changed between
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// runs.
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func (obj *ListLookupFunc) Build(typ *types.Type) (*types.Type, error) {
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// typ is the KindFunc signature we're trying to build...
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if typ.Kind != types.KindFunc {
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return nil, fmt.Errorf("input type must be of kind func")
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}
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if obj.hasDefault == nil {
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return nil, fmt.Errorf("the listlookup function needs exactly two or three args")
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}
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if *obj.hasDefault && len(typ.Ord) != 3 {
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return nil, fmt.Errorf("the listlookup function needs exactly three args")
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}
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if !*obj.hasDefault && len(typ.Ord) != 2 {
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return nil, fmt.Errorf("the listlookup function needs exactly two args")
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}
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if typ.Out == nil {
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return nil, fmt.Errorf("return type of function must be specified")
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}
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if typ.Map == nil {
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return nil, fmt.Errorf("invalid input type")
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}
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tList, exists := typ.Map[typ.Ord[0]]
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if !exists || tList == nil {
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return nil, fmt.Errorf("first arg must be specified")
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}
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tIndex, exists := typ.Map[typ.Ord[1]]
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if !exists || tIndex == nil {
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return nil, fmt.Errorf("second arg must be specified")
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}
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if tIndex != nil && tIndex.Kind != types.KindInt {
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return nil, fmt.Errorf("index must be int kind")
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}
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if err := tList.Val.Cmp(typ.Out); err != nil {
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return nil, errwrap.Wrapf(err, "return type must match list val type")
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}
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if *obj.hasDefault {
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tDefault, exists := typ.Map[typ.Ord[2]]
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if !exists || tDefault == nil {
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return nil, fmt.Errorf("third arg must be specified")
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}
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if err := tList.Val.Cmp(tDefault); err != nil {
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return nil, errwrap.Wrapf(err, "default must match list val type")
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}
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}
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obj.Type = tList // list type
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return obj.sig(), nil
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}
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// Copy is implemented so that the obj.hasDefault value is not lost if we copy
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// this function. That value is learned during FuncInfer, and previously would
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// have been lost by the time we used it in Build.
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func (obj *ListLookupFunc) Copy() interfaces.Func {
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return &ListLookupFunc{
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Type: obj.Type, // don't copy because we use this after unification
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hasDefault: obj.hasDefault,
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init: obj.init, // likely gets overwritten anyways
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}
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}
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// Validate tells us if the input struct takes a valid form.
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func (obj *ListLookupFunc) Validate() error {
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if obj.Type == nil { // build must be run first
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return fmt.Errorf("type is still unspecified")
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}
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if obj.Type.Kind != types.KindList {
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return fmt.Errorf("type must be a kind of list")
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}
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if obj.hasDefault == nil {
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return fmt.Errorf("function not built correctly")
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}
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return nil
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}
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// Info returns some static info about itself. Build must be called before this
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// will return correct data.
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func (obj *ListLookupFunc) Info() *interfaces.Info {
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return &interfaces.Info{
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Pure: true,
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Memo: false,
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Sig: obj.sig(), // helper
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Err: obj.Validate(),
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}
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}
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// Init runs some startup code for this function.
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func (obj *ListLookupFunc) Init(init *interfaces.Init) error {
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obj.init = init
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return nil
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}
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// Stream returns the changing values that this func has over time.
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func (obj *ListLookupFunc) Stream(ctx context.Context) error {
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defer close(obj.init.Output) // the sender closes
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for {
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select {
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case input, ok := <-obj.init.Input:
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if !ok {
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return nil // can't output any more
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}
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//if err := input.Type().Cmp(obj.Info().Sig.Input); err != nil {
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// return errwrap.Wrapf(err, "wrong function input")
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//}
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if obj.last != nil && input.Cmp(obj.last) == nil {
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continue // value didn't change, skip it
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}
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obj.last = input // store for next
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l := (input.Struct()[listLookupArgNameList]).(*types.ListValue)
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index := input.Struct()[listLookupArgNameIndex].Int()
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//zero := l.Type().New() // the zero value
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// TODO: should we handle overflow by returning zero?
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if index > math.MaxInt { // max int size varies by arch
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return fmt.Errorf("list index overflow, got: %d, max is: %d", index, math.MaxInt)
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}
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if index < 0 {
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return fmt.Errorf("list index was negative, got: %d", index)
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}
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|
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// negative index values are "not found" here!
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var result types.Value
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val, exists := l.Lookup(int(index))
|
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if exists {
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result = val
|
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} else if *obj.hasDefault {
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result = input.Struct()[listLookupArgNameDefault]
|
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} else {
|
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return fmt.Errorf("list index not present, got: %d, len is: %d", index, len(l.List()))
|
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}
|
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|
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// if previous input was `2 + 4`, but now it
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// changed to `1 + 5`, the result is still the
|
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// same, so we can skip sending an update...
|
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if obj.result != nil && result.Cmp(obj.result) == nil {
|
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continue // result didn't change
|
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}
|
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obj.result = result // store new result
|
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|
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case <-ctx.Done():
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return nil
|
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}
|
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select {
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case obj.init.Output <- obj.result: // send
|
||||
case <-ctx.Done():
|
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return nil
|
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}
|
||||
}
|
||||
}
|
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35
lang/core/map/map.go
Normal file
35
lang/core/map/map.go
Normal file
@@ -0,0 +1,35 @@
|
||||
// Mgmt
|
||||
// Copyright (C) 2013-2024+ James Shubin and the project contributors
|
||||
// Written by James Shubin <james@shubin.ca> and the project contributors
|
||||
//
|
||||
// This program is free software: you can redistribute it and/or modify
|
||||
// it under the terms of the GNU General Public License as published by
|
||||
// the Free Software Foundation, either version 3 of the License, or
|
||||
// (at your option) any later version.
|
||||
//
|
||||
// This program is distributed in the hope that it will be useful,
|
||||
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
// GNU General Public License for more details.
|
||||
//
|
||||
// You should have received a copy of the GNU General Public License
|
||||
// along with this program. If not, see <https://www.gnu.org/licenses/>.
|
||||
//
|
||||
// Additional permission under GNU GPL version 3 section 7
|
||||
//
|
||||
// If you modify this program, or any covered work, by linking or combining it
|
||||
// with embedded mcl code and modules (and that the embedded mcl code and
|
||||
// modules which link with this program, contain a copy of their source code in
|
||||
// the authoritative form) containing parts covered by the terms of any other
|
||||
// license, the licensors of this program grant you additional permission to
|
||||
// convey the resulting work. Furthermore, the licensors of this program grant
|
||||
// the original author, James Shubin, additional permission to update this
|
||||
// additional permission if he deems it necessary to achieve the goals of this
|
||||
// additional permission.
|
||||
|
||||
package coremap
|
||||
|
||||
const (
|
||||
// ModuleName is the prefix given to all the functions in this module.
|
||||
ModuleName = "map"
|
||||
)
|
||||
299
lang/core/map/map_lookup_func.go
Normal file
299
lang/core/map/map_lookup_func.go
Normal file
@@ -0,0 +1,299 @@
|
||||
// Mgmt
|
||||
// Copyright (C) 2013-2024+ James Shubin and the project contributors
|
||||
// Written by James Shubin <james@shubin.ca> and the project contributors
|
||||
//
|
||||
// This program is free software: you can redistribute it and/or modify
|
||||
// it under the terms of the GNU General Public License as published by
|
||||
// the Free Software Foundation, either version 3 of the License, or
|
||||
// (at your option) any later version.
|
||||
//
|
||||
// This program is distributed in the hope that it will be useful,
|
||||
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
// GNU General Public License for more details.
|
||||
//
|
||||
// You should have received a copy of the GNU General Public License
|
||||
// along with this program. If not, see <https://www.gnu.org/licenses/>.
|
||||
//
|
||||
// Additional permission under GNU GPL version 3 section 7
|
||||
//
|
||||
// If you modify this program, or any covered work, by linking or combining it
|
||||
// with embedded mcl code and modules (and that the embedded mcl code and
|
||||
// modules which link with this program, contain a copy of their source code in
|
||||
// the authoritative form) containing parts covered by the terms of any other
|
||||
// license, the licensors of this program grant you additional permission to
|
||||
// convey the resulting work. Furthermore, the licensors of this program grant
|
||||
// the original author, James Shubin, additional permission to update this
|
||||
// additional permission if he deems it necessary to achieve the goals of this
|
||||
// additional permission.
|
||||
|
||||
package coremap
|
||||
|
||||
import (
|
||||
"context"
|
||||
"fmt"
|
||||
|
||||
"github.com/purpleidea/mgmt/lang/funcs"
|
||||
"github.com/purpleidea/mgmt/lang/interfaces"
|
||||
"github.com/purpleidea/mgmt/lang/types"
|
||||
"github.com/purpleidea/mgmt/util/errwrap"
|
||||
)
|
||||
|
||||
const (
|
||||
// MapLookupFuncName is the name this function is registered as.
|
||||
MapLookupFuncName = "lookup" // map.lookup
|
||||
|
||||
// arg names...
|
||||
mapLookupArgNameMap = "map"
|
||||
mapLookupArgNameKey = "key"
|
||||
mapLookupArgNameDef = "default"
|
||||
)
|
||||
|
||||
func init() {
|
||||
funcs.ModuleRegister(ModuleName, MapLookupFuncName, func() interfaces.Func { return &MapLookupFunc{} }) // must register the func and name
|
||||
}
|
||||
|
||||
var _ interfaces.BuildableFunc = &MapLookupFunc{} // ensure it meets this expectation
|
||||
|
||||
// MapLookupFunc is a key map lookup function. It can take either two or three
|
||||
// arguments. The first argument is the map to lookup a value by key in. The
|
||||
// second is the key to use. If you specify a third argument, then this value
|
||||
// will be returned if the map key is not present. If the third argument is
|
||||
// omitted, then this function errors if the map key is not present.
|
||||
type MapLookupFunc struct {
|
||||
Type *types.Type // Kind == Map, that is used as the map we lookup
|
||||
|
||||
hasDefault *bool // does this function take a third arg?
|
||||
|
||||
init *interfaces.Init
|
||||
last types.Value // last value received to use for diff
|
||||
|
||||
result types.Value // last calculated output
|
||||
}
|
||||
|
||||
// String returns a simple name for this function. This is needed so this struct
|
||||
// can satisfy the pgraph.Vertex interface.
|
||||
func (obj *MapLookupFunc) String() string {
|
||||
return MapLookupFuncName
|
||||
}
|
||||
|
||||
// ArgGen returns the Nth arg name for this function.
|
||||
func (obj *MapLookupFunc) ArgGen(index int) (string, error) {
|
||||
seq := []string{mapLookupArgNameMap, mapLookupArgNameKey, mapLookupArgNameDef}
|
||||
if l := len(seq); index >= l {
|
||||
return "", fmt.Errorf("index %d exceeds arg length of %d", index, l)
|
||||
}
|
||||
return seq[index], nil
|
||||
}
|
||||
|
||||
// helper
|
||||
func (obj *MapLookupFunc) sig() *types.Type {
|
||||
// func(map map{?1: ?2}, key ?1) ?2
|
||||
// OR
|
||||
// func(map map{?1: ?2}, key ?1, default ?2) ?2
|
||||
|
||||
if obj.hasDefault == nil { // not yet known
|
||||
return nil
|
||||
}
|
||||
|
||||
k := "?1"
|
||||
v := "?2"
|
||||
m := fmt.Sprintf("map{%s: %s}", k, v)
|
||||
if obj.Type != nil { // don't panic if called speculatively
|
||||
k = obj.Type.Key.String()
|
||||
v = obj.Type.Val.String()
|
||||
m = obj.Type.String()
|
||||
}
|
||||
|
||||
if *obj.hasDefault {
|
||||
return types.NewType(fmt.Sprintf(
|
||||
"func(%s %s, %s %s, %s %s) %s",
|
||||
mapLookupArgNameMap, m,
|
||||
mapLookupArgNameKey, k,
|
||||
mapLookupArgNameDef, v,
|
||||
v,
|
||||
))
|
||||
}
|
||||
|
||||
return types.NewType(fmt.Sprintf(
|
||||
"func(%s %s, %s %s) %s",
|
||||
mapLookupArgNameMap, m,
|
||||
mapLookupArgNameKey, k,
|
||||
v,
|
||||
))
|
||||
}
|
||||
|
||||
// FuncInfer takes partial type and value information from the call site of this
|
||||
// function so that it can build an appropriate type signature for it. The type
|
||||
// signature may include unification variables.
|
||||
func (obj *MapLookupFunc) FuncInfer(partialType *types.Type, partialValues []types.Value) (*types.Type, []*interfaces.UnificationInvariant, error) {
|
||||
if l := len(partialValues); l != 2 && l != 3 {
|
||||
return nil, nil, fmt.Errorf("function must have either 2 or 3 args")
|
||||
}
|
||||
|
||||
b := false
|
||||
//if len(partialValues) == 2 {
|
||||
// b = false
|
||||
//}
|
||||
if len(partialValues) == 3 {
|
||||
b = true
|
||||
}
|
||||
obj.hasDefault = &b // store for later
|
||||
|
||||
return obj.sig(), []*interfaces.UnificationInvariant{}, nil
|
||||
}
|
||||
|
||||
// Build is run to turn the polymorphic, undetermined function, into the
|
||||
// specific statically typed version. It is usually run after Unify completes,
|
||||
// and must be run before Info() and any of the other Func interface methods are
|
||||
// used. This function is idempotent, as long as the arg isn't changed between
|
||||
// runs.
|
||||
func (obj *MapLookupFunc) Build(typ *types.Type) (*types.Type, error) {
|
||||
// typ is the KindFunc signature we're trying to build...
|
||||
if typ.Kind != types.KindFunc {
|
||||
return nil, fmt.Errorf("input type must be of kind func")
|
||||
}
|
||||
|
||||
if obj.hasDefault == nil {
|
||||
return nil, fmt.Errorf("the maplookup function needs exactly two or three args")
|
||||
}
|
||||
if *obj.hasDefault && len(typ.Ord) != 3 {
|
||||
return nil, fmt.Errorf("the maplookup function needs exactly three args")
|
||||
}
|
||||
if !*obj.hasDefault && len(typ.Ord) != 2 {
|
||||
return nil, fmt.Errorf("the maplookup function needs exactly two args")
|
||||
}
|
||||
|
||||
if typ.Out == nil {
|
||||
return nil, fmt.Errorf("return type of function must be specified")
|
||||
}
|
||||
if typ.Map == nil {
|
||||
return nil, fmt.Errorf("invalid input type")
|
||||
}
|
||||
|
||||
tMap, exists := typ.Map[typ.Ord[0]]
|
||||
if !exists || tMap == nil {
|
||||
return nil, fmt.Errorf("first arg must be specified")
|
||||
}
|
||||
|
||||
tKey, exists := typ.Map[typ.Ord[1]]
|
||||
if !exists || tKey == nil {
|
||||
return nil, fmt.Errorf("second arg must be specified")
|
||||
}
|
||||
|
||||
if err := tMap.Key.Cmp(tKey); err != nil {
|
||||
return nil, errwrap.Wrapf(err, "key must match map key type")
|
||||
}
|
||||
|
||||
if err := tMap.Val.Cmp(typ.Out); err != nil {
|
||||
return nil, errwrap.Wrapf(err, "return type must match map val type")
|
||||
}
|
||||
|
||||
if *obj.hasDefault {
|
||||
tDef, exists := typ.Map[typ.Ord[2]]
|
||||
if !exists || tDef == nil {
|
||||
return nil, fmt.Errorf("third arg must be specified")
|
||||
}
|
||||
if err := tMap.Val.Cmp(tDef); err != nil {
|
||||
return nil, errwrap.Wrapf(err, "default must match map val type")
|
||||
}
|
||||
}
|
||||
|
||||
obj.Type = tMap // map type
|
||||
return obj.sig(), nil
|
||||
}
|
||||
|
||||
// Copy is implemented so that the obj.hasDefault value is not lost if we copy
|
||||
// this function. That value is learned during FuncInfer, and previously would
|
||||
// have been lost by the time we used it in Build.
|
||||
func (obj *MapLookupFunc) Copy() interfaces.Func {
|
||||
return &MapLookupFunc{
|
||||
Type: obj.Type, // don't copy because we use this after unification
|
||||
hasDefault: obj.hasDefault,
|
||||
|
||||
init: obj.init, // likely gets overwritten anyways
|
||||
}
|
||||
}
|
||||
|
||||
// Validate tells us if the input struct takes a valid form.
|
||||
func (obj *MapLookupFunc) Validate() error {
|
||||
if obj.Type == nil { // build must be run first
|
||||
return fmt.Errorf("type is still unspecified")
|
||||
}
|
||||
if obj.Type.Kind != types.KindMap {
|
||||
return fmt.Errorf("type must be a kind of map")
|
||||
}
|
||||
if obj.hasDefault == nil {
|
||||
return fmt.Errorf("function not built correctly")
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Info returns some static info about itself. Build must be called before this
|
||||
// will return correct data.
|
||||
func (obj *MapLookupFunc) Info() *interfaces.Info {
|
||||
return &interfaces.Info{
|
||||
Pure: true,
|
||||
Memo: false,
|
||||
Sig: obj.sig(), // helper
|
||||
Err: obj.Validate(),
|
||||
}
|
||||
}
|
||||
|
||||
// Init runs some startup code for this function.
|
||||
func (obj *MapLookupFunc) Init(init *interfaces.Init) error {
|
||||
obj.init = init
|
||||
return nil
|
||||
}
|
||||
|
||||
// Stream returns the changing values that this func has over time.
|
||||
func (obj *MapLookupFunc) Stream(ctx context.Context) error {
|
||||
defer close(obj.init.Output) // the sender closes
|
||||
for {
|
||||
select {
|
||||
case input, ok := <-obj.init.Input:
|
||||
if !ok {
|
||||
return nil // can't output any more
|
||||
}
|
||||
//if err := input.Type().Cmp(obj.Info().Sig.Input); err != nil {
|
||||
// return errwrap.Wrapf(err, "wrong function input")
|
||||
//}
|
||||
|
||||
if obj.last != nil && input.Cmp(obj.last) == nil {
|
||||
continue // value didn't change, skip it
|
||||
}
|
||||
obj.last = input // store for next
|
||||
|
||||
m := (input.Struct()[mapLookupArgNameMap]).(*types.MapValue)
|
||||
key := input.Struct()[mapLookupArgNameKey]
|
||||
//zero := m.Type().New() // the zero value
|
||||
|
||||
var result types.Value
|
||||
val, exists := m.Lookup(key)
|
||||
if exists {
|
||||
result = val
|
||||
} else if *obj.hasDefault {
|
||||
result = input.Struct()[mapLookupArgNameDef]
|
||||
} else {
|
||||
return fmt.Errorf("map key not present, got: %v", key)
|
||||
}
|
||||
|
||||
// if previous input was `2 + 4`, but now it
|
||||
// changed to `1 + 5`, the result is still the
|
||||
// same, so we can skip sending an update...
|
||||
if obj.result != nil && result.Cmp(obj.result) == nil {
|
||||
continue // result didn't change
|
||||
}
|
||||
obj.result = result // store new result
|
||||
|
||||
case <-ctx.Done():
|
||||
return nil
|
||||
}
|
||||
|
||||
select {
|
||||
case obj.init.Output <- obj.result: // send
|
||||
case <-ctx.Done():
|
||||
return nil
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user