Documentation
¶
Overview ¶
Package parser is an AWK parser and abstract syntax tree.
Use the ParseProgram function to parse an AWK program, and then give the result to one of the interp.Exec* functions to execute it.
Example (Error) ¶
package main
import (
"fmt"
"github.com/benhoyt/goawk/parser"
)
func main() {
prog, err := parser.ParseProgram([]byte("{ for if }"), nil)
if err != nil {
fmt.Println(err)
} else {
fmt.Println(prog)
}
}
Output: parse error at 1:7: expected ( instead of if
Example (Valid) ¶
package main
import (
"fmt"
"github.com/benhoyt/goawk/parser"
)
func main() {
prog, err := parser.ParseProgram([]byte("$0 { print $1 }"), nil)
if err != nil {
fmt.Println(err)
} else {
fmt.Println(prog)
}
}
Output: $0 { print $1 }
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type ParseError ¶
type ParseError struct {
// Source line/column position where the error occurred.
Position Position
// Error message.
Message string
}
ParseError (actually *ParseError) is the type of error returned by ParseProgram.
func (*ParseError) Error ¶
func (e *ParseError) Error() string
Error returns a formatted version of the error, including the line and column numbers.
type ParserConfig ¶
type ParserConfig struct {
// Enable printing of type information
DebugTypes bool
// io.Writer to print type information on (for example, os.Stderr)
DebugWriter io.Writer
// Map of named Go functions to allow calling from AWK. See docs
// on interp.Config.Funcs for details.
Funcs map[string]interface{}
}
ParserConfig lets you specify configuration for the parsing process (for example printing type information for debugging).
type Program ¶
type Program struct {
// These fields aren't intended to be used or modified directly,
// but are exported for the interpreter (Program itself needs to
// be exported in package "parser", otherwise these could live in
// "internal/ast".)
Begin []Stmts
Actions []Action
End []Stmts
Functions []Function
Scalars map[string]int
Arrays map[string]int
}
Program is the abstract syntax tree for an entire AWK program.
func ParseProgram ¶
func ParseProgram(src []byte, config *ParserConfig) (prog *Program, err error)
ParseProgram parses an entire AWK program, returning the *Program abstract syntax tree or a *ParseError on error. "config" describes the parser configuration (and is allowed to be nil).
Source Files