github.com/MontFerret/ferret@v0.18.0/pkg/stdlib/arrays/first.go (about)

     1  package arrays
     2  
     3  import (
     4  	"context"
     5  
     6  	"github.com/MontFerret/ferret/pkg/runtime/core"
     7  	"github.com/MontFerret/ferret/pkg/runtime/values"
     8  	"github.com/MontFerret/ferret/pkg/runtime/values/types"
     9  )
    10  
    11  // FIRST returns a first element from a given array.
    12  // @param {Any[]} arr - Target array.
    13  // @return {Any} - First element in a given array.
    14  func First(_ context.Context, args ...core.Value) (core.Value, error) {
    15  	err := core.ValidateArgs(args, 1, 1)
    16  
    17  	if err != nil {
    18  		return values.None, err
    19  	}
    20  
    21  	err = core.ValidateType(args[0], types.Array)
    22  
    23  	if err != nil {
    24  		return values.None, nil
    25  	}
    26  
    27  	arr := args[0].(*values.Array)
    28  
    29  	return arr.Get(0), nil
    30  }