diff --git a/Readme.md b/Readme.md
index e0d032e..63d0b30 100644
--- a/Readme.md
+++ b/Readme.md
@@ -43,12 +43,17 @@ Use the `func` function from the stdlib:
In this case, `(form_to_be_evaluated)` will not be evaluated until the function is called.
### Control flow
-See `stdlib/control_flow.go`. We have if and while forms:
+See `stdlib/control_flow.go`. We have if, while, and progn forms:
`(if (cond) (then) (else))`
`(when (cond) (form1)....... (formN))`
-
+`(progn (form1)..... (formN))`
+If and While should be self explanatory. For those new to LISP, the rough idea of progn is to evaluate a sequence of N forms and return the result of the final one.
We also have functioning implementations of map and reduce in the stdlib (incomplete)
+## Comments
+The standard delimiter for comments is ;
+any characters after a semicolon will be ignored until end of line
+
## How to build
### Compiling/Installation
- For now simply run `go install cmd/...` for each utility you wish to use. If you have GOPATH and GOBIN set it should be usable from PATH
@@ -69,9 +74,14 @@ We also have functioning implementations of map and reduce in the stdlib (incomp
* one can write arbitrary shs script into `.shsrc` including function and variable declarations
* of note are the following variables
- `SH_LOGGING` Sets the log level (from 0 to 3)
- - `SHS_SH_PROMPT` Sets the prompt
+ - `SHS_STATIC_PROMPT` Sets the prompt
- `SH_HIST_FILE` Sets the history file
- - `SH_DEBUG_MODE` Adds additional debug output for the lexer
+ - `SH_DEBUG_MODE` Adds additional debug output for the lexer (high clutter)
+* additionally, the repl will evaluate any function you define as `_SH_PROMPT` before the shell prompt
+ - if defined, the function will be evaluated before printing the prompt
+ - the function will be given 0 arguments
+ - if the function does not return a string, its output will be discarded
+ - afterwards, the repl will print the values in `SHS_STATIC_PROMPT`
Here is an example of a shs configuration file:
```lisp
(export GOPATH (concat HOME "/go"))
@@ -80,6 +90,8 @@ Here is an example of a shs configuration file:
(export GIT_TERMINAL_PROMPT 1)
(export SH_HIST_FILE (concat HOME "/.shs_hist"))
(export SH_LOGGING 0)
+(export SHS_STATIC_PROMPT ">")
+(func _SH_PROMPT () (concat (?) ($ basename ($ pwd)) "\n"))
```
## Contributing
diff --git a/ast/eval.go b/ast/eval.go
index 0f6cc98..e82a89b 100644
--- a/ast/eval.go
+++ b/ast/eval.go
@@ -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
@@ -61,6 +63,8 @@ func (in *Token) Eval(funcs FuncTable, vars VarTable, cnvtUndefVars bool) *Token
"eval")
return nil
}
+ } else {
+ res.Next = in.Next
}
case LIST:
diff --git a/ast/func_table.go b/ast/func_table.go
index b70f758..b939e0c 100644
--- a/ast/func_table.go
+++ b/ast/func_table.go
@@ -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 {
@@ -75,3 +97,18 @@ func GetFunction(arg string, table FuncTable) *Function {
return target
}
+
+
+/* returns list of all functions in table
+ */
+func ListFuncs(ft FuncTable) []string {
+ keys := make([]string, len(*ft))
+ i := 0
+
+ for k := range *ft {
+ keys[i] = k
+ i++
+ }
+
+ return keys
+}
diff --git a/ast/lex.go b/ast/lex.go
index 532f32a..3031cab 100644
--- a/ast/lex.go
+++ b/ast/lex.go
@@ -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 {
@@ -121,6 +125,17 @@ func lex(input string) *Token {
return -2
}
+ // returns the end of the string OR the end of the line
+ matchLineEnd := func(start int) int {
+ for i := start; i < len(input); i++ {
+ if input[i] == '\n' {
+ return i
+ }
+ }
+
+ return len(input)
+ }
+
needs_alloc := false
start_pos := 0
for i := 0; i < len(input); i++ {
@@ -137,13 +152,18 @@ func lex(input string) *Token {
is_str = true
needs_alloc = true
- case ' ':
+ case ' ', '\n', '\t', '\v', '\f', '\r':
if i == start_pos {
start_pos += 1
continue
}
needs_alloc = true
+
+ // comment case
+ case ';':
+ start_pos = i + 1
+ i = matchLineEnd(start_pos)
}
if needs_alloc {
@@ -185,6 +205,7 @@ error:
return nil
}
+// returns true if a string could contain an int or float
func StrIsNumber(arg string) bool {
dotCount := 0
diff --git a/ast/print.go b/ast/print.go
index 944b698..ea5251c 100644
--- a/ast/print.go
+++ b/ast/print.go
@@ -18,6 +18,7 @@
package ast
import (
+ "fmt"
"strings"
)
@@ -49,7 +50,7 @@ loop:
constructor.WriteString(iter.FmtToken())
}
- println(constructor.String())
+ fmt.Printf(constructor.String() + "\n")
goto loop
}
diff --git a/ast/token.go b/ast/token.go
index 367cd42..b9ba0ca 100644
--- a/ast/token.go
+++ b/ast/token.go
@@ -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
diff --git a/ast/tokenstack.go b/ast/tokenstack.go
index 9f7360b..136ccae 100644
--- a/ast/tokenstack.go
+++ b/ast/tokenstack.go
@@ -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
diff --git a/ast/var_table.go b/ast/var_table.go
index 7037e4a..f597eee 100644
--- a/ast/var_table.go
+++ b/ast/var_table.go
@@ -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 &&
@@ -73,22 +83,21 @@ func SetVar(variable string, value *Token, vt VarTable) {
}
}
-// 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
- }
+/* lists all vars in tables
+ */
+func ListVars(vt VarTable) []string {
+ keys := make([]string, len(*vt))
+ i := 0
+ for k := range *vt {
+ keys[i] = k
}
- return res
+ return keys
}
+/* if SyncTablesWithOSEnviron is true
+ * function will put ever environment variable into VarTable
+ */
func InitVarTable(table VarTable) {
if !SyncTablesWithOSEnviron {
return
@@ -122,6 +131,9 @@ func DeleteVarTable(table VarTable) {
}
}
+/* removes var from vartable
+ * if SyncTablesWithOSENviron is true, also unsets environment variable
+ */
func RemoveVar(arg string, table VarTable) {
if SyncTablesWithOSEnviron {
err := os.Unsetenv(arg)
diff --git a/cmd/shs_repl.go b/cmd/shs.go
similarity index 60%
rename from cmd/shs_repl.go
rename to cmd/shs.go
index ea6007c..3379c7c 100644
--- a/cmd/shs_repl.go
+++ b/cmd/shs.go
@@ -18,11 +18,13 @@
package main
import (
+ "os"
"fmt"
"strconv"
- "github.com/chzyer/readline"
+ "github.com/peterh/liner"
"gitlab.com/whom/shs/ast"
"gitlab.com/whom/shs/log"
+ "gitlab.com/whom/shs/util"
"gitlab.com/whom/shs/config"
)
@@ -30,6 +32,22 @@ const (
def_prompt string = "λ "
)
+
+// useful for when input contains escape sequences
+// not checking delims cause thats up to the user who defines their prompts
+func parseString(in string) string {
+ in = "\"" + in + "\""
+ out, err := strconv.Unquote(in)
+ if err != nil {
+ log.Log(log.ERR,
+ "Couldnt parse (pre?)prompt",
+ "init")
+ return ""
+ }
+
+ return out
+}
+
func setLogLvl(vars ast.VarTable) {
var loglvl string
@@ -54,6 +72,7 @@ func main() {
var prompt string
var debug string
var hist string
+ no_hist := false
ast.SyncTablesWithOSEnviron = true
ast.ExecWhenFuncUndef = true
@@ -67,34 +86,62 @@ func main() {
hist_t := ast.GetVar("SH_HIST_FILE", vars)
if hist_t != nil {
hist = hist_t.Value()
+ } else {
+ no_hist = true
}
- prompt_t := ast.GetVar("SHS_SH_PROMPT", vars)
+ dyn_prompt := ast.GetFunction("_SH_PROMPT", funcs)
+ if dyn_prompt == nil || dyn_prompt.Args != 0 {
+ dyn_prompt = nil
+ }
+
+ prompt_t := ast.GetVar("SHS_STATIC_PROMPT", vars)
if prompt_t != nil {
- prompt = prompt_t.Value()
+ prompt = parseString(prompt_t.Value())
} else {
prompt = def_prompt
}
- rl, err := readline.NewEx(&readline.Config{
- Prompt: prompt,
- HistoryFile: hist,
- InterruptPrompt: "^C",
+ line := liner.NewLiner()
+ defer line.Close()
+
+ line.SetCtrlCAborts(true)
+ line.SetCompleter(func(line string) (c []string) {
+ return util.ShellCompleter(line, vars, funcs)
})
- defer rl.Close()
- if err != nil {
- log.Log(log.ERR, "Couldnt initialize readline: " + err.Error(), "repl")
- return
+ var histFile *os.File
+ var err error
+ if !no_hist {
+ histFile, err = os.Open(hist)
+ if err == nil {
+ line.ReadHistory(histFile)
+ } else {
+ log.Log(log.ERR,
+ "couldnt read history: " + err.Error(),
+ "repl")
+ }
+ defer histFile.Close()
}
for {
setLogLvl(vars)
- text, err := rl.Readline()
- if err != nil {
- log.Log(log.ERR, "couldnt read user input: " + err.Error(), "repl")
+ var prePrompt string
+ if dyn_prompt != nil {
+ p_tok := dyn_prompt.CallFunction(nil, vars, funcs)
+ if p_tok != nil && p_tok.Tag == ast.STRING {
+ prePrompt = parseString(p_tok.Value())
+ }
}
+ fmt.Printf(prePrompt)
+ text, err := line.Prompt(prompt)
+ if err != nil && err != liner.ErrPromptAborted{
+ log.Log(log.ERR, "couldnt read user input: " + err.Error(), "repl")
+ continue
+ }
+
+ line.AppendHistory(text)
userInput := ast.Lex(text)
if userInput == nil {
// errors handled in Lex
diff --git a/config/config.go b/config/config.go
index 6ce7d51..fc8eda3 100644
--- a/config/config.go
+++ b/config/config.go
@@ -18,14 +18,16 @@
package config
import (
- "os"
- "io"
- "bufio"
"gitlab.com/whom/shs/log"
"gitlab.com/whom/shs/ast"
+ "gitlab.com/whom/shs/util"
"gitlab.com/whom/shs/stdlib"
)
+/* creates new VarTable and FuncTable
+ * reads a configuration file
+ * executes contents and returns tables
+ */
func InitFromConfig(configFile string) (ast.VarTable, ast.FuncTable) {
funcs := stdlib.GenFuncTable()
vars := &map[string]*ast.Token{}
@@ -35,32 +37,10 @@ func InitFromConfig(configFile string) (ast.VarTable, ast.FuncTable) {
p := ast.GetVar("HOME", vars)
configFile = p.Value() + "/" + configFile
- cfile, err := os.Open(configFile)
- if err != nil {
- log.Log(log.DEBUG,
- "unable to open config file: " + err.Error(),
- "config")
- return vars, funcs
- }
-
- r := bufio.NewReader(cfile)
- text, err := r.ReadString('\n')
- for err != io.EOF {
- if err != nil {
- log.Log(log.ERR,
- "unable to read from config file: " + err.Error(),
- "config")
- break
- }
-
- // Eval lines in config
- ast.Lex(text).Eval(funcs, vars, false)
- text, err = r.ReadString('\n')
- }
+ util.LoadScript(configFile, vars, funcs)
log.Log(log.DEBUG,
"config file fully evaluated",
"config")
- cfile.Close()
return vars, funcs
}
diff --git a/go.mod b/go.mod
index 125370b..2b85407 100644
--- a/go.mod
+++ b/go.mod
@@ -2,4 +2,7 @@ module gitlab.com/whom/shs
go 1.14
-require github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e // indirect
+require (
+ github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e // indirect
+ github.com/peterh/liner v1.2.0 // indirect
+)
diff --git a/go.sum b/go.sum
index 454fe40..285b298 100644
--- a/go.sum
+++ b/go.sum
@@ -1,2 +1,6 @@
github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e h1:fY5BOSpyZCqRo5OhCuC+XN+r/bBCmeuuJtjz+bCNIf8=
github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
+github.com/mattn/go-runewidth v0.0.3 h1:a+kO+98RDGEfo6asOGMmpodZq4FNtnGP54yps8BzLR4=
+github.com/mattn/go-runewidth v0.0.3/go.mod h1:LwmH8dsx7+W8Uxz3IHJYH5QSwggIsqBzpuz5H//U1FU=
+github.com/peterh/liner v1.2.0 h1:w/UPXyl5GfahFxcTOz2j9wCIHNI+pUPr2laqpojKNCg=
+github.com/peterh/liner v1.2.0/go.mod h1:CRroGNssyjTd/qIG2FyxByd2S8JEAZXBl4qUrZf8GS0=
diff --git a/log/logger.go b/log/logger.go
index 5f3d773..2d736e6 100644
--- a/log/logger.go
+++ b/log/logger.go
@@ -29,16 +29,23 @@ const (
var logLevel int64
+/* Set the log level from 0 to 4
+ * currently only 0, 1, and 2 are used.
+ */
func SetLogLvl(lvl int64) {
if lvl < 4 && lvl > 0 {
logLevel = lvl
}
}
+/* get current log level as int
+ */
func GetLogLvl() int64 {
return logLevel
}
+/* writes a message to the log
+ */
func Log(lvl int, msg, context string) {
if int64(lvl) > logLevel {
return
diff --git a/stdlib/arith.go b/stdlib/arith.go
index 7a61754..d516551 100644
--- a/stdlib/arith.go
+++ b/stdlib/arith.go
@@ -29,7 +29,40 @@ import (
// perhaps we simply write out arithmetic routines that operate on the strings
// then we need not worry about storage length.
-func add(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
+/* Takes 1 argument (must be a string)
+ * will attempt to cast it to a number.
+ * will return nil if cast fails
+ *
+ * Example: (number "3.4")
+ */
+func NumCast(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
+ in = in.Eval(f, a, false)
+ if in.Tag != ast.STRING {
+ log.Log(log.ERR,
+ "only a string can successfully be cast to a number",
+ "number_cast")
+ return nil
+ }
+
+ if !ast.StrIsNumber(in.Value()) {
+ log.Log(log.ERR,
+ "string failed number cast",
+ "number_cast")
+ return nil
+ }
+
+ out := in.Copy()
+ out.Tag = ast.NUMBER
+ return out
+}
+
+/* adds N number arguments
+ * takes N arguments
+ * returns the sum, or nil if improper arguments were given
+ *
+ * Example: (+ 1 2)
+ */
+func Add(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
var res float64
in = in.Eval(f, a, false)
@@ -71,7 +104,12 @@ func add(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
return t
}
-func sub(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
+/* subtract N args from the final arg
+ * takes N args, returns nil if improper args given
+ *
+ * Example: (- 2 1)
+ */
+func Sub(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
var res float64
var sub float64
@@ -121,7 +159,12 @@ func sub(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
return t
}
-func mult(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
+/* multiplies N arguments
+ * returns nil if an improper argument is given
+ *
+ * Example: (* 1 2)
+ */
+func Mult(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
res := 1.0
in = in.Eval(f, a, false)
@@ -163,7 +206,13 @@ func mult(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
return t
}
-func div(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
+/* divide N arguments
+ * the first argument is divided by each subsequent argument in order
+ * returns nil if an improper argument is given
+ *
+ * Example (/ 25 5)
+ */
+func Div(in *ast.Token, a ast.VarTable, f ast.FuncTable) *ast.Token {
var res float64
in = in.Eval(f, a, false)
diff --git a/stdlib/bool.go b/stdlib/bool.go
index 328c4e7..d6b07e6 100644
--- a/stdlib/bool.go
+++ b/stdlib/bool.go
@@ -23,7 +23,35 @@ import (
"gitlab.com/whom/shs/ast"
)
-func not(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes one argument, must be a string
+ * attempts to cast to bool (T or F are valid values)
+ * returns nil on failure
+ *
+ * Example: (bool "F")
+ */
+func BoolCast(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ in = in.Eval(ft, vt, false)
+ if in.Tag == ast.LIST || in.Tag == ast.NUMBER {
+ log.Log(log.ERR,
+ "only strings successfully cast to bool",
+ "bool cast")
+ return nil
+ }
+
+ body := in.Value()
+ if body != ast.TRUE && body != ast.FALSE {
+ log.Log(log.ERR,
+ "cast to bool failed",
+ "bool cast")
+ return nil
+ }
+
+ res := &ast.Token{ Tag: ast.BOOL }
+ res.Set(body)
+ return res
+}
+
+func Not(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, false)
if in.Tag != ast.BOOL {
@@ -41,7 +69,7 @@ func not(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return t
}
-func eq(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+func Eq(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
out := ast.TRUE
in = in.Eval(ft, vt, false)
@@ -123,7 +151,7 @@ func eq(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return t
}
-func lt(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+func Lt(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
out := ast.TRUE
second := in.Next
@@ -146,7 +174,7 @@ func lt(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return t
}
-func gt(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+func Gt(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
out := ast.TRUE
second := in.Next
@@ -169,14 +197,14 @@ func gt(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return t
}
-func ne(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
- return not(eq(in, vt, ft), vt, ft)
+func Ne(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ return Not(Eq(in, vt, ft), vt, ft)
}
-func gte(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
- return not(lt(in, vt, ft), vt, ft)
+func Gte(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ return Not(Lt(in, vt, ft), vt, ft)
}
-func lte(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
- return not(gt(in, vt, ft), vt, ft)
+func Lte(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ return Not(Gt(in, vt, ft), vt, ft)
}
diff --git a/stdlib/call.go b/stdlib/call.go
index 4359503..99e0647 100644
--- a/stdlib/call.go
+++ b/stdlib/call.go
@@ -30,7 +30,6 @@ import (
)
var bgProcs = make([]*exec.Cmd, 0)
-var LastExitCode int
var sigs = []os.Signal{
os.Interrupt,
syscall.SIGTERM,
@@ -40,8 +39,17 @@ var sigs = []os.Signal{
syscall.SIGCONT,
}
+/* Exit code of last run process
+ */
+var LastExitCode int
-func call(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes n arguments (list of tokens generated by lexing a shell command)
+ * Evaluates arguments, but does not err on undefined symbols (note the last arg to Eval(...))
+ * Executes shell command and returns nil
+ *
+ * Example (l vim file.txt)
+ */
+func Call(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, true)
if in == nil {
return nil
@@ -74,9 +82,10 @@ func call(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
} else {
cmd = exec.Command(path)
}
+ cmd.Env = os.Environ()
+ cmd.Stdin = os.Stdin
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
- cmd.Stdin = os.Stdin
signalChan := make(chan os.Signal, 2)
signal.Notify(signalChan, sigs...)
@@ -99,7 +108,12 @@ func call(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return nil
}
-func bgcall(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Starts a call in the background
+ * Takes n args (a shell command not delimited by string delimiters)
+ *
+ * Example: (bg vim file.txt)
+ */
+func Bgcall(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
if in == nil {
return nil
}
@@ -143,7 +157,14 @@ func bgcall(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return nil
}
-func fg(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* brings last BG'ed process into the foreground
+ * returns nil
+ *
+ * Example:
+ * (bg vim file.txt)
+ * (fg)
+ */
+func Fg(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
if len(bgProcs) < 1 {
return nil
}
@@ -173,7 +194,16 @@ func fg(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return nil
}
-func jobs(in *ast.Token, vt ast.VarTable, fg ast.FuncTable) *ast.Token {
+/* Takes 0 args
+ * returns a string containing info about current jobs
+ * returns total jobs as well as their PIDs and place in the bg queue
+ *
+ * Example:
+ * (bg ping google.com)
+ * (bg .........)
+ * (jobs)
+ */
+func Jobs(in *ast.Token, vt ast.VarTable, fg ast.FuncTable) *ast.Token {
ret := &ast.Token{
Tag: ast.LIST,
}
@@ -197,7 +227,12 @@ func jobs(in *ast.Token, vt ast.VarTable, fg ast.FuncTable) *ast.Token {
return ret
}
-func read_cmd(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* calls a command (blocks until completion)
+ * captures stdout and returns it as a string
+ *
+ * Example: ($ echo hello world)
+ */
+func ReadCmd(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, true)
if in == nil {
@@ -254,19 +289,37 @@ func read_cmd(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
}
}
+ output := out.String()
+ olen := len(output)
+ if olen > 0 && output[olen - 1] == '\n' {
+ output = output[:olen - 1]
+ }
+
ret := &ast.Token{Tag: ast.STRING}
- ret.Set(out.String())
+ ret.Set(output)
return ret
}
-func get_exit(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes 0 arguments
+ * returns the exit code of the last executed program
+ *
+ * Example:
+ * (sudo apt update)
+ * (?) <- gets exit code
+ */
+func GetExit(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
ret := &ast.Token{Tag: ast.NUMBER}
ret.Set(fmt.Sprintf("%d", LastExitCode))
return ret
}
-func kill(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* takes an argument (pid of process to be killed)
+ * calls Process.Kill() on it
+ * do not use this if you already have a native implementation
+ * (this function not added to functable in stdlib.go)
+ */
+func Kill(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, true)
if in.Tag == ast.LIST {
diff --git a/stdlib/control_flow.go b/stdlib/control_flow.go
index 5889e33..0238ff5 100644
--- a/stdlib/control_flow.go
+++ b/stdlib/control_flow.go
@@ -22,9 +22,29 @@ import (
"gitlab.com/whom/shs/log"
)
-/* return one evaluated form or another based on the boolean statement
+/* eval N forms. return the last one
+ *
+ * Example:
+ * (progn (print "hello") (print "world") (+ 1 2))
+ * This example will print "hello world" to stdout and return 3
*/
-func shs_if(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+func ShsProgn(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ var res *ast.Token
+ for iter := in; iter != nil; iter = iter.Next {
+ res = iter.Eval(ft, vt, false)
+ }
+
+ return res
+}
+
+/* return one evaluated form or another based on the boolean statement
+ * arg 1 is a boolean cond, arg 2 is evaluated if the cond is true, arg 3 is evaluated if cond is not true
+ * in total it takes 3 arguments
+ *
+ * Example:
+ * (if (eq (number "3") 3) (print "test passed") (print "test failed"))
+ */
+func ShsIf(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
cond := in
t := cond.Next
f := t.Next
@@ -55,8 +75,14 @@ func shs_if(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
}
/* continually eval n forms while element #1 evals to T
+ * has rather progn like behavior in that it returns the result of the last form to be evaluated
+ *
+ * Example:
+ * (export cond F)
+ * (while cond (export cond T) (print "will only be printed once") (+ 1 2))
+ * loop will iter one time, print "will only be printed once" and return 3
*/
-func shs_while(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+func ShsWhile(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
cond := in
forms := in.Next
in.Next = nil
diff --git a/stdlib/filesys.go b/stdlib/filesys.go
index 6504221..182cdca 100644
--- a/stdlib/filesys.go
+++ b/stdlib/filesys.go
@@ -46,7 +46,14 @@ func AbsPath(arg string) string {
return arg
}
-func cd(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes one arg, returns nil
+ * changes directory to the path in the arg
+ * fails if arg is not stringable
+ *
+ * Example:
+ * (cd (concat HOME "/go"))
+ */
+func Cd(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, true)
if in == nil {
@@ -68,11 +75,19 @@ func cd(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return nil
}
-func fexists(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes one arg, returns a bool
+ * Returns true if arg is a filepath that exists
+ * returns nil if arg is not a string type
+ *
+ * Example:
+ * (touch test)
+ * (fexists test)
+ */
+func Fexists(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, false)
- if in == nil || (in.Tag != ast.NUMBER && in.Tag != ast.STRING) {
+ if in == nil || in.Tag != ast.STRING {
log.Log(log.ERR,
- "argument to fexists must be a string or number",
+ "argument to fexists must be a string",
"fexists")
return nil
}
@@ -92,9 +107,16 @@ func fexists(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return ret
}
-func fread(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes one arg, returns a string
+ * Returns contents of file in arg
+ * returns nil if file doesnt exist
+ *
+ * Example:
+ * (fread (concat HOME ".shsrc"))
+ */
+func Fread(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, false)
- exists := fexists(in, vt, ft) // some waste, extra use of Eval
+ exists := Fexists(in, vt, ft) // some waste, extra use of Eval
if exists == nil || exists.Tag != ast.BOOL || exists.Value() == ast.FALSE {
log.Log(log.ERR,
"error calling fexists or file doesnt exist",
@@ -116,7 +138,14 @@ func fread(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return ret
}
-func fwrite(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes two arguments a filepath and a string
+ * CLOBBERS FILE CONTENTS
+ * Returns nil
+ *
+ * Example:
+ * (fwrite "test" "one two three")
+ */
+func Fwrite(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, false)
if in == nil || in.Tag == ast.SYMBOL || in.Tag == ast.LIST {
log.Log(log.ERR,
@@ -146,7 +175,14 @@ func fwrite(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return nil
}
-func fappend(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes two arguments a filepath and a string
+ * DOES NOT CLOBBER FILE CONTENTS
+ * Returns nil
+ *
+ * Example:
+ * (fwrite "test" "one two three")
+ */
+func Fappend(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, false)
if in == nil || in.Tag == ast.SYMBOL || in.Tag == ast.LIST {
log.Log(log.ERR,
@@ -163,7 +199,7 @@ func fappend(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return nil
}
- exists := fexists(in, vt, ft)
+ exists := Fexists(in, vt, ft)
if exists.Value() == ast.FALSE {
log.Log(log.ERR,
"file "+in.Value()+" does not exist",
diff --git a/stdlib/funcs.go b/stdlib/funcs.go
index 93de50d..63f3130 100644
--- a/stdlib/funcs.go
+++ b/stdlib/funcs.go
@@ -22,7 +22,17 @@ import (
"gitlab.com/whom/shs/log"
)
-func decl_func(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
+/* Takes 3 arguments: name, list of arg names, and logic form
+ * DOES NOT EVALUATE THE LOGIC FORM
+ * adds an anonymous function to the FuncTable under the name specified
+ * anonymous function will expect the args declared in arg2 and expand them in arg3
+ * Then evaluates and returns result of arg3. This constitutes a function call
+ *
+ * Example:
+ * (func foo (x) (print x))
+ * (foo 4) -> prints 4
+ */
+func DeclFunc(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
name := input
if name.Tag != ast.SYMBOL {
log.Log(log.ERR,
@@ -60,30 +70,34 @@ func decl_func(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.To
ASTSYNCSTATE := ast.SyncTablesWithOSEnviron
inner := func(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
- temp := in.Eval(ft, vt, false)
- if temp == nil {
- log.Log(log.ERR,
- "error parsing arguments",
- name.Value())
- return nil
- }
-
- ast.SyncTablesWithOSEnviron = false
- key_iter := args.Expand()
- val_iter := temp
-
- for key_iter != nil {
- if val_iter == nil {
+ var temp *ast.Token
+ if numArgs != 0 || in != nil {
+ temp = in.Eval(ft, vt, false)
+ if temp == nil {
log.Log(log.ERR,
- "Not enough arguments supplied",
+ "error parsing arguments",
name.Value())
+ return nil
}
- ast.SetVar(key_iter.Value(), val_iter, vt)
- key_iter = key_iter.Next
- val_iter = val_iter.Next
+ ast.SyncTablesWithOSEnviron = false
+ key_iter := args.Expand()
+ val_iter := temp
+
+ for key_iter != nil {
+ if val_iter == nil {
+ log.Log(log.ERR,
+ "Not enough arguments supplied",
+ name.Value())
+ }
+
+ ast.SetVar(key_iter.Value(), val_iter, vt)
+ key_iter = key_iter.Next
+ val_iter = val_iter.Next
+ }
}
+ // maybe we actually should put the inner scope var into the env
ast.SyncTablesWithOSEnviron = ASTSYNCSTATE
ret := form.Eval(ft, vt, false)
ast.SyncTablesWithOSEnviron = false
diff --git a/stdlib/list.go b/stdlib/list.go
index ac20d28..cec7d80 100644
--- a/stdlib/list.go
+++ b/stdlib/list.go
@@ -27,7 +27,7 @@ import (
* retuns a sequence of elements (list contents)
* in event a not-list is passed in, returns the arg.
*/
-func expand(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
+func Expand(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
if input.Tag != ast.LIST {
log.Log(log.DEBUG, "expand called on not a list", "expand")
return input
@@ -41,7 +41,7 @@ func expand(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token
* Arg one is a list, next args are appended
* if no args are a list, a list is made from all args
*/
-func l_append(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
+func L_append(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
src := input
if input.Tag != ast.LIST {
diff --git a/stdlib/stdlib.go b/stdlib/stdlib.go
index 5ad08a5..83749c2 100644
--- a/stdlib/stdlib.go
+++ b/stdlib/stdlib.go
@@ -22,202 +22,234 @@ import (
"fmt"
"gitlab.com/whom/shs/log"
"gitlab.com/whom/shs/ast"
+ "gitlab.com/whom/shs/util"
)
+/* Makes a FuncTable from all functions in the stdlib
+ * add your function here if you are extending the standard library
+ */
func GenFuncTable() ast.FuncTable {
var stdlib ast.FuncTable
stdlib = &map[string]*ast.Function{
"if": &ast.Function{
- Function: shs_if,
+ Function: ShsIf,
Name: "if",
TimesCalled: 0,
Args: 3,
},
"while": &ast.Function{
- Function: shs_while,
+ Function: ShsWhile,
Name: "while",
TimesCalled: 0,
Args: -1,
},
- "eval": &ast.Function{
- Function: eval,
- Name: "eval",
- TimesCalled: 0,
- Args: -1,
+ "progn": &ast.Function{
+ Function: ShsProgn,
+ Name: "shs_progn",
+ TimesCalled: 0,
+ Args: -1,
},
"func": &ast.Function{
- Function: decl_func,
+ Function: DeclFunc,
Name: "decl_func",
TimesCalled: 0,
Args: 3,
},
"export": &ast.Function{
- Function: export,
+ Function: Export,
Name: "export",
TimesCalled: 0,
Args: 2,
},
- "input": &ast.Function{
- Function: input,
+ "input": &ast.Function{
+ Function: Input,
Name: "input",
TimesCalled: 0,
Args: 1,
},
- "...": &ast.Function{
- Function: expand,
+ "load": &ast.Function{
+ Function: Load,
+ Name: "load",
+ TimesCalled: 0,
+ Args: 1,
+ },
+
+ "bool": &ast.Function{
+ Function: BoolCast,
+ Name: "bool",
+ TimesCalled: 0,
+ Args: 1,
+ },
+
+ "string": &ast.Function{
+ Function: StrCast,
+ Name: "string",
+ TimesCalled: 0,
+ Args: 1,
+ },
+
+ "number": &ast.Function{
+ Function: NumCast,
+ Name: "number",
+ TimesCalled: 0,
+ Args: 1,
+ },
+
+ "...": &ast.Function{
+ Function: Expand,
Name: "...",
TimesCalled: 0,
Args: 1,
},
"append": &ast.Function{
- Function: l_append,
+ Function: L_append,
Name: "append",
TimesCalled: 0,
Args: -1,
},
"exit": &ast.Function{
- Function: exit_shell,
+ Function: ExitShell,
Name: "exit",
TimesCalled: 0,
Args: 0,
},
"eq": &ast.Function{
- Function: eq,
+ Function: Eq,
Name: "==",
TimesCalled: 0,
Args: 2,
},
"ne": &ast.Function{
- Function: ne,
+ Function: Ne,
Name: "!=",
TimesCalled: 0,
Args: 2,
},
"<": &ast.Function{
- Function: lt,
+ Function: Lt,
Name: "<",
TimesCalled: 0,
Args: 2,
},
">": &ast.Function{
- Function: gt,
+ Function: Gt,
Name: ">",
TimesCalled: 0,
Args: 2,
},
"<=": &ast.Function{
- Function: lte,
+ Function: Lte,
Name: "<=",
TimesCalled: 0,
Args: 2,
},
">=": &ast.Function{
- Function: gte,
+ Function: Gte,
Name: ">=",
TimesCalled: 0,
Args: 2,
},
"!": &ast.Function{
- Function: not,
+ Function: Not,
Name: "!",
TimesCalled: 0,
Args: 1,
},
"+": &ast.Function{
- Function: add,
+ Function: Add,
Name: "add",
TimesCalled: 0,
Args: -1,
},
"-": &ast.Function{
- Function: sub,
+ Function: Sub,
Name: "sub",
TimesCalled: 0,
Args: -1,
},
"*": &ast.Function{
- Function: mult,
+ Function: Mult,
Name: "mult",
TimesCalled: 0,
Args: -1,
},
"/": &ast.Function{
- Function: div,
+ Function: Div,
Name: "div",
TimesCalled: 0,
Args: -1,
},
"cd": &ast.Function{
- Function: cd,
+ Function: Cd,
Name: "changedir",
TimesCalled: 0,
Args: 1,
},
"concat": &ast.Function{
- Function: concat,
+ Function: Concat,
Name:"concatenate",
TimesCalled: 0,
Args: -1,
},
"print": &ast.Function{
- Function:print_str,
+ Function: PrintStr,
Name: "print",
TimesCalled: 0,
Args: 1,
},
"l": &ast.Function{
- Function: call,
+ Function: Call,
Name: "call",
TimesCalled: 0,
Args: -1,
},
"bg": &ast.Function{
- Function: bgcall,
+ Function: Bgcall,
Name: "background call",
TimesCalled: 0,
Args: -1,
},
"fg": &ast.Function{
- Function: fg,
+ Function: Fg,
Name: "foreground",
TimesCalled: 0,
Args: 0,
},
"$": &ast.Function{
- Function: read_cmd,
+ Function: ReadCmd,
Name: "read cmd",
TimesCalled: 0,
Args: -1,
},
"?": &ast.Function{
- Function: get_exit,
+ Function: GetExit,
Name:"get exit code",
TimesCalled: 0,
Args: 0,
@@ -234,42 +266,42 @@ func GenFuncTable() ast.FuncTable {
*/
"jobs": &ast.Function{
- Function: jobs,
+ Function: Jobs,
Name: "list jobs",
TimesCalled: 0,
Args: 0,
},
"info": &ast.Function{
- Function: sh_info,
+ Function: ShInfo,
Name: "Shell Info",
TimesCalled: 0,
Args: 1,
},
"fexists": &ast.Function{
- Function: fexists,
+ Function: Fexists,
Name: "file exists",
TimesCalled: 0,
Args: 1,
},
"fread": &ast.Function{
- Function: fread,
+ Function: Fread,
Name: "read file",
TimesCalled: 0,
Args: 1,
},
"fwrite": &ast.Function{
- Function: fwrite,
+ Function: Fwrite,
Name: "write file",
TimesCalled: 0,
Args: 2,
},
"fappend": &ast.Function{
- Function: fappend,
+ Function: Fappend,
Name:"append to file",
TimesCalled: 0,
Args: 2,
@@ -279,12 +311,22 @@ func GenFuncTable() ast.FuncTable {
return stdlib
}
-func exit_shell(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* takes no args
+ * exits shell when called
+ *
+ * Example: (exit)
+ */
+func ExitShell(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
os.Exit(0)
return nil // I hope execution doesnt get here
}
-func sh_info(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* takes one arg, doesnt evaluate it
+ * returns type or metadata
+ *
+ * Example: (info append)
+ */
+func ShInfo(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
switch in.Tag {
case ast.BOOL:
fmt.Printf("BOOL LITERAL\nValue: %s\n", in.Value())
@@ -314,11 +356,14 @@ func sh_info(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return nil
}
-func eval(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
- return in.Eval(ft, vt, false)
-}
-
-func input(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Takes 1 arg, uses it as a prompt
+ * errs if prompt is not a string or number
+ * gets a line from stdin
+ * returns it as a string
+ *
+ * Example: (print (input))
+ */
+func Input(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, false)
if in.Tag != ast.STRING && in.Tag != ast.NUMBER {
log.Log(log.ERR,
@@ -337,3 +382,23 @@ func input(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
ret.Set(output)
return ret
}
+
+/* Takes 1 arg, returns nil
+ * if arg is a valid existing file than load will execute it as a script
+ *
+ * Example: (load "myscript.shs")
+ */
+func Load(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ in = in.Eval(ft, vt, true)
+ if in.Tag != ast.STRING {
+ log.Log(log.ERR,
+ "argument to load must be a string",
+ "load")
+ return nil
+ }
+
+ bp := in.Value()
+ bp = AbsPath(bp)
+ util.LoadScript(bp, vt, ft)
+ return nil
+}
diff --git a/stdlib/string.go b/stdlib/string.go
index b8321d7..3cae616 100644
--- a/stdlib/string.go
+++ b/stdlib/string.go
@@ -19,11 +19,16 @@ package stdlib
import (
"fmt"
+ "strconv"
"gitlab.com/whom/shs/ast"
"gitlab.com/whom/shs/log"
)
-func concat(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+/* Concatenates N stringables
+ *
+ * Example: (concat "hello" " " "world")
+ */
+func Concat(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
in = in.Eval(ft, vt, false)
var res string
@@ -42,7 +47,38 @@ func concat(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
return t
}
-func print_str(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
- fmt.Println(in.Eval(ft, vt, false))
+/* Takes 1 argument, returns its value as a string
+ * works on lists too.
+ *
+ * Example: (string 1) -> 1.0
+ */
+func StrCast(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ body := in.Eval(ft, vt, false).String()
+ res := &ast.Token{ Tag: ast.STRING }
+ res.Set(body)
+ return res
+}
+
+/* Takes one arg, returns nil
+ * Prints a string to stdout
+ * Unquotes string so user can add escaped chars like \n, \t, etc
+ *
+ * Example: (print "Line: \n, Tab: \t")
+ */
+func PrintStr(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+ body := in.Eval(ft, vt, false).String()
+ if body[0] != body[len(body)-1] && body[0] != '"' {
+ body = "`" + body + "`"
+ }
+
+ text, err := strconv.Unquote(body)
+ if err != nil {
+ log.Log(log.ERR,
+ "error unquoting string",
+ "print")
+ return nil
+ }
+
+ fmt.Printf(text + "\n")
return nil
}
diff --git a/stdlib/vars.go b/stdlib/vars.go
index 6aed9f9..52938f2 100644
--- a/stdlib/vars.go
+++ b/stdlib/vars.go
@@ -22,7 +22,15 @@ import (
"gitlab.com/whom/shs/log"
)
-func export(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
+/* Takes 2 args, a name and a value
+ * Exports a varable
+ * both args are evaluated
+ *
+ * Example:
+ * (export hw (concat "hello" " " "world"))
+ * (print hw)
+ */
+func Export(input *ast.Token, vars ast.VarTable, funcs ast.FuncTable) *ast.Token {
name := input
form := name.Next.Eval(funcs, vars, false)
diff --git a/util/scripts.go b/util/scripts.go
new file mode 100644
index 0000000..3d2115b
--- /dev/null
+++ b/util/scripts.go
@@ -0,0 +1,52 @@
+/* SHS: Syntactically Homogeneous Shell
+ * Copyright (C) 2019 Aidan Hahn
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
+ */
+
+package util
+
+import (
+ "os"
+ "io/ioutil"
+ "gitlab.com/whom/shs/log"
+ "gitlab.com/whom/shs/ast"
+)
+
+/* Opens a file and lexes+evaluates the contents
+ */
+func LoadScript(path string, vt ast.VarTable, ft ast.FuncTable) {
+ scriptFile, err := os.Open(path)
+ if err != nil {
+ log.Log(log.ERR,
+ "unable to open script: " + err.Error(),
+ "util")
+ return
+ }
+
+ var body []byte
+ body, err = ioutil.ReadFile(path)
+ scriptFile.Close()
+ if err != nil {
+ log.Log(log.ERR,
+ "unable to read script: " + err.Error(),
+ "util")
+ return
+ }
+
+ set := ast.Lex(string(body))
+ for iter := set; iter != nil; iter = iter.Next {
+ iter.Eval(ft, vt, false)
+ }
+}
diff --git a/util/shell_complete.go b/util/shell_complete.go
new file mode 100644
index 0000000..a6e3289
--- /dev/null
+++ b/util/shell_complete.go
@@ -0,0 +1,102 @@
+/* SHS: Syntactically Homogeneous Shell
+ * Copyright (C) 2019 Aidan Hahn
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
+ */
+
+package util
+
+import (
+ "strings"
+ "io/ioutil"
+ "gitlab.com/whom/shs/log"
+ "gitlab.com/whom/shs/ast"
+)
+
+/* gathers completions for the last word in a given line
+ * shell wraps this in a lambda that passes in the vt and ft
+ * I suppose it could be more optimal. Fix if it bothers you
+ */
+func ShellCompleter(line string, vt ast.VarTable, ft ast.FuncTable) []string {
+ var head, tail string
+
+ idx := strings.LastIndex(line, " ")
+ if idx > 0 {
+ head = line[:idx+1]
+ tail = line[idx+1:]
+ } else {
+ head = ""
+ tail = line
+ }
+
+ dir, path, tok := getPathBase(tail)
+ compSource := []string{}
+
+ if !path {
+ dir = "."
+ } else {
+ line = tok
+ }
+
+ fobjs, err := ioutil.ReadDir(dir)
+ if err != nil {
+ log.Log(log.DEBUG,
+ "couldnt read dir " + dir + ": " + err.Error(),
+ "complete")
+ if path {
+ return nil
+ }
+ } else {
+ for _, f := range fobjs {
+ compSource = append(compSource, dir + "/" + f.Name())
+ }
+ }
+
+ if !path {
+ compSource = append(compSource, ast.ListVars(vt)...)
+ compSource = append(compSource, ast.ListFuncs(ft)...)
+ }
+
+ completions := []string{}
+ for _, i := range compSource {
+ if strings.HasPrefix(i, tail) {
+ completions = append(completions, head + i)
+ }
+ }
+
+ return completions
+}
+
+// returns everything up to the last '/'
+// as well as whether or not a / was found
+// and finally the token after the last /
+func getPathBase(in string) (string, bool, string) {
+ if in == "" {
+ return "", false, ""
+ }
+
+ isPath := false
+
+ i := len(in) - 1
+ for i > 0 {
+ if in[i] == '/' {
+ isPath = true
+ break
+ }
+
+ i -= 1
+ }
+
+ return in[:i], isPath, in[i+1:]
+}