github.com/MontFerret/ferret@v0.18.0/pkg/compiler/compiler.go (about)

     1  package compiler
     2  
     3  import (
     4  	"github.com/pkg/errors"
     5  
     6  	"github.com/MontFerret/ferret/pkg/parser"
     7  	"github.com/MontFerret/ferret/pkg/runtime"
     8  	"github.com/MontFerret/ferret/pkg/runtime/core"
     9  	"github.com/MontFerret/ferret/pkg/stdlib"
    10  )
    11  
    12  type Compiler struct {
    13  	*NamespaceContainer
    14  }
    15  
    16  func New(setters ...Option) *Compiler {
    17  	c := &Compiler{}
    18  	c.NamespaceContainer = newRootNamespace()
    19  	c.funcs = core.NewFunctions()
    20  
    21  	opts := &Options{}
    22  
    23  	for _, setter := range setters {
    24  		setter(opts)
    25  	}
    26  
    27  	if !opts.noStdlib {
    28  		if err := stdlib.RegisterLib(c.NamespaceContainer); err != nil {
    29  			panic(err)
    30  		}
    31  	}
    32  
    33  	return c
    34  }
    35  
    36  func (c *Compiler) Compile(query string) (program *runtime.Program, err error) {
    37  	if query == "" {
    38  		return nil, ErrEmptyQuery
    39  	}
    40  
    41  	defer func() {
    42  		if r := recover(); r != nil {
    43  			// find out exactly what the error was and set err
    44  			switch x := r.(type) {
    45  			case string:
    46  				err = errors.New(x)
    47  			case error:
    48  				err = x
    49  			default:
    50  				err = errors.New("unknown panic")
    51  			}
    52  
    53  			program = nil
    54  		}
    55  	}()
    56  
    57  	p := parser.New(query)
    58  	p.AddErrorListener(newErrorListener())
    59  
    60  	l := newVisitor(query, c.funcs)
    61  
    62  	res := p.Visit(l).(*result)
    63  
    64  	if res.Ok() {
    65  		program = res.Data().(*runtime.Program)
    66  	} else {
    67  		err = res.Error()
    68  	}
    69  
    70  	return program, err
    71  }
    72  
    73  func (c *Compiler) MustCompile(query string) *runtime.Program {
    74  	program, err := c.Compile(query)
    75  
    76  	if err != nil {
    77  		panic(err)
    78  	}
    79  
    80  	return program
    81  }