added

vendor/github.com/glycerine/zygomys/zygo/slurp.go

@@ -0,0 +1,169 @@
+package zygo
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+)
+
+// read new-line delimited text from a file into an array (slurpf "path-to-file")
+func SlurpfileFunction(env *Zlisp, name string, args []Sexp) (Sexp, error) {
+	if len(args) != 1 {
+		return SexpNull, WrongNargs
+	}
+	var fn string
+	switch fna := args[0].(type) {
+	case *SexpStr:
+		fn = fna.S
+	default:
+		return SexpNull, fmt.Errorf("slurp requires a string path to read. we got type %T / value = %v", args[0], args[0])
+	}
+
+	if !FileExists(string(fn)) {
+		return SexpNull, fmt.Errorf("file '%s' does not exist", fn)
+	}
+	f, err := os.Open(fn)
+	if err != nil {
+		return SexpNull, err
+	}
+	defer f.Close()
+
+	a := make([]Sexp, 0)
+
+	bufIn := bufio.NewReader(f)
+	lineNum := int64(1)
+	for {
+		lastline, err := bufIn.ReadBytes('\n')
+		if err != nil && err != io.EOF {
+			return SexpNull, err
+		}
+		n := len(lastline)
+		if err == io.EOF && n == 0 {
+			break
+		}
+		if n > 0 {
+			if lastline[n-1] == '\n' {
+				a = append(a, &SexpStr{S: string(lastline[:n-1])})
+			} else {
+				a = append(a, &SexpStr{S: string(lastline)})
+			}
+			lineNum += 1
+		}
+
+		if err == io.EOF {
+			break
+		}
+	}
+
+	VPrintf("read %d lines\n", lineNum)
+	return env.NewSexpArray(a), nil
+}
+
+// (writef <content> path); (write path) is the macro version.
+// (owritef <content> path): write an array of strings out to the named file,
+// overwriting it in the process. (owrite) is the macro version.
+// save is the same as write.
+func WriteToFileFunction(env *Zlisp, name string, args []Sexp) (Sexp, error) {
+	if len(args) != 2 {
+		return SexpNull, WrongNargs
+	}
+	var fn string
+	switch fna := args[1].(type) {
+	case *SexpStr:
+		fn = fna.S
+	default:
+		return SexpNull, fmt.Errorf("owrite requires a string (SexpStr) path to write to as the second argument. we got type %T / value = %v", args[1], args[1])
+	}
+
+	if name == "write" || name == "writef" || name == "save" {
+		// don't overwrite existing file
+		if FileExists(fn) {
+			return SexpNull, fmt.Errorf("refusing to write to existing file '%s'",
+				fn)
+		}
+	}
+	// owrite / owritef overwrite indiscriminately.
+
+	f, err := os.Create(fn)
+	if err != nil {
+		return SexpNull, err
+	}
+	defer f.Close()
+
+	var slice []Sexp
+	switch sl := args[0].(type) {
+	case *SexpArray:
+		slice = sl.Val
+		for i := range slice {
+			s := slice[i].SexpString(nil)
+			if len(s) >= 2 && s[0] == '"' && s[len(s)-1] == '"' {
+				s = s[1 : len(s)-1]
+			} else if len(s) >= 2 && s[0] == '`' && s[len(s)-1] == '`' {
+				s = s[1 : len(s)-1]
+			}
+			_, err = fmt.Fprintf(f, "%s\n", s)
+			if err != nil {
+				return SexpNull, err
+			}
+		}
+	case *SexpRaw:
+		_, err = f.Write([]byte(sl.Val))
+		if err != nil {
+			return SexpNull, err
+		}
+
+	default:
+		s := sl.SexpString(nil)
+		if len(s) >= 2 && s[0] == '"' && s[len(s)-1] == '"' {
+			s = s[1 : len(s)-1]
+		} else if len(s) >= 2 && s[0] == '`' && s[len(s)-1] == '`' {
+			s = s[1 : len(s)-1]
+		}
+		_, err = fmt.Fprintf(f, "%s\n", s)
+		if err != nil {
+			return SexpNull, err
+		}
+	}
+
+	return SexpNull, nil
+}
+
+// SplitStringFunction splits a string based on an arbitrary delimiter
+func SplitStringFunction(env *Zlisp, name string, args []Sexp) (Sexp, error) {
+	if len(args) != 2 {
+		return SexpNull, WrongNargs
+	}
+
+	// make sure the two args are strings
+	s1, ok := args[0].(*SexpStr)
+	if !ok {
+		return SexpNull, fmt.Errorf("split requires a string to split, got %T", args[0])
+	}
+	s2, ok := args[1].(*SexpStr)
+	if !ok {
+		return SexpNull, fmt.Errorf("split requires a string as a delimiter, got %T", args[1])
+	}
+
+	toSplit := s1.S
+	splitter := s2.S
+	s := strings.Split(toSplit, splitter)
+
+	split := make([]Sexp, len(s))
+	for i := range split {
+		split[i] = &SexpStr{S: s[i]}
+	}
+
+	return env.NewSexpArray(split), nil
+}
+
+// (nsplit "a\nb") -> ["a" "b"]
+func SplitStringOnNewlinesFunction(env *Zlisp, name string, args []Sexp) (Sexp, error) {
+	if len(args) != 1 {
+		return SexpNull, WrongNargs
+	}
+	args = append(args, &SexpStr{S: "\n"})
+
+	return SplitStringFunction(env, name, args)
+}