github.com/hugorut/terraform@v1.1.3/src/lang/funcs/string.go (about)

     1  package funcs
     2  
     3  import (
     4  	"regexp"
     5  	"strings"
     6  
     7  	"github.com/zclconf/go-cty/cty"
     8  	"github.com/zclconf/go-cty/cty/function"
     9  )
    10  
    11  // ReplaceFunc constructs a function that searches a given string for another
    12  // given substring, and replaces each occurence with a given replacement string.
    13  var ReplaceFunc = function.New(&function.Spec{
    14  	Params: []function.Parameter{
    15  		{
    16  			Name: "str",
    17  			Type: cty.String,
    18  		},
    19  		{
    20  			Name: "substr",
    21  			Type: cty.String,
    22  		},
    23  		{
    24  			Name: "replace",
    25  			Type: cty.String,
    26  		},
    27  	},
    28  	Type: function.StaticReturnType(cty.String),
    29  	Impl: func(args []cty.Value, retType cty.Type) (ret cty.Value, err error) {
    30  		str := args[0].AsString()
    31  		substr := args[1].AsString()
    32  		replace := args[2].AsString()
    33  
    34  		// We search/replace using a regexp if the string is surrounded
    35  		// in forward slashes.
    36  		if len(substr) > 1 && substr[0] == '/' && substr[len(substr)-1] == '/' {
    37  			re, err := regexp.Compile(substr[1 : len(substr)-1])
    38  			if err != nil {
    39  				return cty.UnknownVal(cty.String), err
    40  			}
    41  
    42  			return cty.StringVal(re.ReplaceAllString(str, replace)), nil
    43  		}
    44  
    45  		return cty.StringVal(strings.Replace(str, substr, replace, -1)), nil
    46  	},
    47  })
    48  
    49  // Replace searches a given string for another given substring,
    50  // and replaces all occurences with a given replacement string.
    51  func Replace(str, substr, replace cty.Value) (cty.Value, error) {
    52  	return ReplaceFunc.Call([]cty.Value{str, substr, replace})
    53  }