| // Copyright 2020 Google LLC |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package examples |
| |
| import ( |
| "fmt" |
| "log" |
| |
| "github.com/google/cel-go/cel" |
| "github.com/google/cel-go/checker/decls" |
| ) |
| |
| func ExampleSimple() { |
| d := cel.Declarations(decls.NewIdent("name", decls.String, nil)) |
| env, err := cel.NewEnv(d) |
| if err != nil { |
| log.Fatalf("environment creation error: %v\n", err) |
| } |
| ast, iss := env.Compile(`"Hello world! I'm " + name + "."`) |
| // Check iss for compilation errors. |
| if iss.Err() != nil { |
| log.Fatalln(iss.Err()) |
| } |
| prg, err := env.Program(ast) |
| if err != nil { |
| log.Fatalln(err) |
| } |
| out, _, err := prg.Eval(map[string]interface{}{ |
| "name": "CEL", |
| }) |
| if err != nil { |
| log.Fatalln(err) |
| } |
| fmt.Println(out) |
| // Output:Hello world! I'm CEL. |
| } |