ast package full godoc
This commit is contained in:
parent
956044cfae
commit
fec3550702
7 changed files with 68 additions and 26 deletions
|
|
@ -19,12 +19,14 @@ package ast
|
|||
|
||||
import "gitlab.com/whom/shs/log"
|
||||
|
||||
/* determines whether or not to execute a system call
|
||||
/* determines whether or not to execute a system binary
|
||||
* when a function cannot be found in the functable
|
||||
* (use case: shell)
|
||||
* ExecFunc determines the name of the system call function to fetch
|
||||
*/
|
||||
var ExecWhenFuncUndef = false
|
||||
|
||||
/* name of the command used to execute a system binary
|
||||
*/
|
||||
var ExecFunc = "l"
|
||||
|
||||
/* Runs through an AST of tokens
|
||||
|
|
|
|||
|
|
@ -19,18 +19,35 @@ package ast
|
|||
|
||||
import "gitlab.com/whom/shs/log"
|
||||
|
||||
/* expected function header for any stdlib function
|
||||
*/
|
||||
type Operation func(*Token, VarTable, FuncTable) *Token
|
||||
|
||||
/* holds a stdlib function along with relevant metadata
|
||||
*/
|
||||
type Function struct {
|
||||
// go function that list of args are passed to
|
||||
Function Operation
|
||||
|
||||
// name of function
|
||||
Name string
|
||||
|
||||
// number of times user has called this function
|
||||
TimesCalled int
|
||||
Args int // TODO: Make this a list of expected types (TAGs)
|
||||
|
||||
// number of args required
|
||||
Args int
|
||||
}
|
||||
|
||||
/* holds a mapping of key to function
|
||||
* passed to eval and into function calls
|
||||
* initialized by repl at startup
|
||||
*/
|
||||
type FuncTable *map[string]*Function
|
||||
|
||||
// TODO: Currently only checks arg list length
|
||||
/* validates an individual call of a function
|
||||
* makes sure correct arguments are passed in
|
||||
*/
|
||||
func (f Function) ParseFunction(args *Token) bool {
|
||||
// handle infinite args
|
||||
if f.Args < 0 {
|
||||
|
|
@ -52,6 +69,9 @@ func (f Function) ParseFunction(args *Token) bool {
|
|||
return true
|
||||
}
|
||||
|
||||
/* handles a call to a function
|
||||
* calls ParseFunction and increments TimesCalled
|
||||
*/
|
||||
func (f Function) CallFunction(args *Token, vt VarTable, ft FuncTable) *Token {
|
||||
if !f.ParseFunction(args) {
|
||||
log.Log(log.ERR,
|
||||
|
|
@ -64,6 +84,8 @@ func (f Function) CallFunction(args *Token, vt VarTable, ft FuncTable) *Token {
|
|||
return f.Function(args, vt, ft)
|
||||
}
|
||||
|
||||
/* searches for function mapped to argument in FuncTable
|
||||
*/
|
||||
func GetFunction(arg string, table FuncTable) *Function {
|
||||
target, ok := (*table)[arg]
|
||||
if !ok {
|
||||
|
|
@ -77,7 +99,7 @@ func GetFunction(arg string, table FuncTable) *Function {
|
|||
}
|
||||
|
||||
|
||||
/* lists all functions in table
|
||||
/* returns list of all functions in table
|
||||
*/
|
||||
func ListFuncs(ft FuncTable) []string {
|
||||
keys := make([]string, len(*ft))
|
||||
|
|
|
|||
|
|
@ -22,8 +22,12 @@ import (
|
|||
"unicode"
|
||||
)
|
||||
|
||||
// all delimiters that work on strings
|
||||
const string_delims string = "\"'`"
|
||||
|
||||
/* takes a line of user input
|
||||
* returns an unsimplified tree of tokens
|
||||
*/
|
||||
func Lex(input string) *Token {
|
||||
ret := lex(input)
|
||||
if ret == nil {
|
||||
|
|
@ -201,6 +205,7 @@ error:
|
|||
return nil
|
||||
}
|
||||
|
||||
// returns true if a string could contain an int or float
|
||||
func StrIsNumber(arg string) bool {
|
||||
dotCount := 0
|
||||
|
||||
|
|
|
|||
|
|
@ -19,7 +19,11 @@ package ast
|
|||
|
||||
import "fmt"
|
||||
|
||||
/* token_t is a tag that declares the type of the
|
||||
* datum contained in a token
|
||||
*/
|
||||
type Token_t int
|
||||
|
||||
const (
|
||||
LIST Token_t = iota
|
||||
STRING Token_t = iota
|
||||
|
|
@ -31,6 +35,9 @@ const (
|
|||
FALSE string = "F"
|
||||
)
|
||||
|
||||
/* Contains a parsed lexeme
|
||||
* and a pointer to the next parsed lexeme in the same scope
|
||||
*/
|
||||
type Token struct {
|
||||
Next *Token
|
||||
Tag Token_t
|
||||
|
|
|
|||
|
|
@ -17,16 +17,23 @@
|
|||
|
||||
package ast
|
||||
|
||||
/* primitive stack type for tokens
|
||||
* useful for iterative algorithms on tokens
|
||||
*/
|
||||
type TokenStack struct {
|
||||
buffer []*Token
|
||||
capacity int
|
||||
}
|
||||
|
||||
/* push token onto stack
|
||||
*/
|
||||
func (s *TokenStack) Push(v *Token) {
|
||||
s.capacity++
|
||||
s.buffer = append(s.buffer, v)
|
||||
}
|
||||
|
||||
/* pop token off stack
|
||||
*/
|
||||
func (s *TokenStack) Pop() *Token {
|
||||
if s.capacity <= 0 {
|
||||
return nil
|
||||
|
|
|
|||
|
|
@ -26,11 +26,19 @@ import (
|
|||
"gitlab.com/whom/shs/log"
|
||||
)
|
||||
|
||||
// Trigger this if you are using this for a shell
|
||||
/* defines whether or not to synchronize tokens wiht os environment vars
|
||||
* will not sync non stringable tokens
|
||||
*/
|
||||
var SyncTablesWithOSEnviron = false
|
||||
|
||||
/* mapping of key to token.
|
||||
*/
|
||||
type VarTable *map[string]*Token
|
||||
|
||||
/* retrieve the token cooresponding to a given key
|
||||
* if SyncTablesWithOSEnviron is true and no token exists for a key
|
||||
* os Environment variables will be searched for the key
|
||||
*/
|
||||
func GetVar(arg string, vt VarTable) *Token {
|
||||
val, ok := (*vt)[arg]
|
||||
if !ok {
|
||||
|
|
@ -55,8 +63,10 @@ func GetVar(arg string, vt VarTable) *Token {
|
|||
return val
|
||||
}
|
||||
|
||||
// TODO: this could be much more optimal
|
||||
// probably a stdlib thing
|
||||
/* adds a key->token mapping to the table
|
||||
* if SyncTablesWithOSEnviron is true, will also add value to os environment
|
||||
* will not do so for non stringable tokens
|
||||
*/
|
||||
func SetVar(variable string, value *Token, vt VarTable) {
|
||||
(*vt)[variable] = value
|
||||
if SyncTablesWithOSEnviron &&
|
||||
|
|
@ -85,22 +95,9 @@ func ListVars(vt VarTable) []string {
|
|||
return keys
|
||||
}
|
||||
|
||||
// Library represents variables defined in inner scope
|
||||
// It is assumed library is ordered from innermost scope to outermost scope
|
||||
func GetVarFromTables(arg string, library []VarTable) *Token {
|
||||
var res *Token
|
||||
res = nil
|
||||
for i := 0; i < len(library); i += 1 {
|
||||
res = GetVar(arg, library[i])
|
||||
if res != nil {
|
||||
// TODO: Log scope res was found in?
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
return res
|
||||
}
|
||||
|
||||
/* if SyncTablesWithOSEnviron is true
|
||||
* function will put ever environment variable into VarTable
|
||||
*/
|
||||
func InitVarTable(table VarTable) {
|
||||
if !SyncTablesWithOSEnviron {
|
||||
return
|
||||
|
|
@ -133,7 +130,10 @@ func DeleteVarTable(table VarTable) {
|
|||
}
|
||||
}
|
||||
}
|
||||
|
||||
a
|
||||
/* removes var from vartable
|
||||
* if SyncTablesWithOSENviron is true, also unsets environment variable
|
||||
*/
|
||||
func RemoveVar(arg string, table VarTable) {
|
||||
if SyncTablesWithOSEnviron {
|
||||
err := os.Unsetenv(arg)
|
||||
|
|
|
|||
|
|
@ -18,7 +18,6 @@
|
|||
package util
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"strings"
|
||||
"io/ioutil"
|
||||
"gitlab.com/whom/shs/log"
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue