github.com/linchen2chris/hugo@v0.0.0-20230307053224-cec209389705/tpl/collections/append.go (about)

     1  // Copyright 2018 The Hugo Authors. All rights reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  // http://www.apache.org/licenses/LICENSE-2.0
     7  //
     8  // Unless required by applicable law or agreed to in writing, software
     9  // distributed under the License is distributed on an "AS IS" BASIS,
    10  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package collections
    15  
    16  import (
    17  	"errors"
    18  
    19  	"github.com/gohugoio/hugo/common/collections"
    20  )
    21  
    22  // Append appends args up to the last one to the slice in the last argument.
    23  // This construct allows template constructs like this:
    24  //
    25  //	{{ $pages = $pages | append $p2 $p1 }}
    26  //
    27  // Note that with 2 arguments where both are slices of the same type,
    28  // the first slice will be appended to the second:
    29  //
    30  //	{{ $pages = $pages | append .Site.RegularPages }}
    31  func (ns *Namespace) Append(args ...any) (any, error) {
    32  	if len(args) < 2 {
    33  		return nil, errors.New("need at least 2 arguments to append")
    34  	}
    35  
    36  	to := args[len(args)-1]
    37  	from := args[:len(args)-1]
    38  
    39  	return collections.Append(to, from...)
    40  }