Add format()

README.md

@@ -1,13 +1,13 @@
 ## calc
 
-[![GoDoc](https://godoc.org/github.com/alfredxing/calc?status.svg)](https://godoc.org/github.com/alfredxing/calc) [![Build Status](https://travis-ci.org/alfredxing/calc.svg?branch=master)](https://travis-ci.org/alfredxing/calc)
+[![GoDoc](https://godoc.org/github.com/denysvitali/calc?status.svg)](https://godoc.org/github.com/denysvitali/calc) [![Build Status](https://travis-ci.org/alfredxing/calc.svg?branch=master)](https://travis-ci.org/alfredxing/calc)
 
 A simple, fast, and intuitive command-line calculator written in Go.
 
 ### Install
 Install calc as you would any other Go program:
 ```
-go get github.com/alfredxing/calc
+go get github.com/denysvitali/calc
 ```
 
 ### Usage

compute/compute.go

@@ -1,6 +1,8 @@
 package compute
 
 import (
+	"encoding/binary"
+	"encoding/hex"
 	"errors"
 	"go/scanner"
 	"go/token"
@@ -9,9 +11,9 @@ import (
 )
 
 import (
-	"github.com/alfredxing/calc/constants"
-	"github.com/alfredxing/calc/operators"
-	"github.com/alfredxing/calc/operators/functions"
+	"github.com/denysvitali/calc/constants"
+	"github.com/denysvitali/calc/operators"
+	"github.com/denysvitali/calc/operators/functions"
 )
 
 var resHistory = []float64{}
@@ -182,6 +184,29 @@ func isNegation(tok token.Token, prev token.Token) bool {
 }
 
 func parseFloat(lit string) (float64, error) {
+	if len(lit) > 2 {
+		if lit[0:2] == "0x" {
+			// Hex
+			hexBytes, err := hex.DecodeString(lit[2:])
+			if err != nil {
+				return 0, errors.New("Cannot parse hex: " + lit)
+			}
+
+			var number []byte
+
+			diff := 8 - len(hexBytes)
+			if diff < 0 {
+				return 0, errors.New("hex exceeds uint64")
+			}
+
+			for i:=0; i<diff; i++ {
+				number = append(number, 0x00)
+			}
+
+			number = append(number, hexBytes...)
+			return float64(binary.BigEndian.Uint64(number)), nil
+		}
+	}
 	f, err := strconv.ParseFloat(lit, 64)
 	if err != nil {
 		return 0, errors.New("Cannot parse recognized float: " + lit)

go.mod

@@ -0,0 +1,10 @@
+module github.com/denysvitali/calc
+
+go 1.20
+
+require golang.org/x/crypto v0.8.0
+
+require (
+	golang.org/x/sys v0.8.0 // indirect
+	golang.org/x/term v0.8.0 // indirect
+)

go.sum

@@ -0,0 +1,6 @@
+golang.org/x/crypto v0.8.0 h1:pd9TJtTueMTVQXzk8E2XESSMQDj/U7OUu0PqJqPXQjQ=
+golang.org/x/crypto v0.8.0/go.mod h1:mRqEX+O9/h5TFCrQhkgjo2yKi0yYA+9ecGkdQoHrywE=
+golang.org/x/sys v0.8.0 h1:EBmGv8NaZBZTWvrbjNoL6HVt+IVy3QDQpJs7VRIw3tU=
+golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.8.0 h1:n5xxQn2i3PC0yLAbjTpNT85q/Kgzcr2gIoX9OrJUols=
+golang.org/x/term v0.8.0/go.mod h1:xPskH00ivmX89bAKVGSKKtLOWNx2+17Eiy94tnKShWo=

main.go

@@ -4,12 +4,13 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"regexp"
 	"strconv"
 	"strings"
 )
 
 import (
-	"github.com/alfredxing/calc/compute"
+	"github.com/denysvitali/calc/compute"
 )
 
 import (
@@ -39,6 +40,10 @@ func main() {
 
 	term := terminal.NewTerminal(os.Stdin, "> ")
 	term.AutoCompleteCallback = handleKey
+
+	format := "G"
+	formatRE := regexp.MustCompile("^format\\((.)\\)$")
+
 	for {
 		text, err := term.ReadLine()
 		if err != nil {
@@ -54,12 +59,25 @@ func main() {
 			break
 		}
 
+		if formatRE.MatchString(text) {
+			matches := formatRE.FindAllStringSubmatch(text, -1)
+			format = matches[0][1]
+			continue
+		}
+
 		res, err := compute.Evaluate(text)
 		if err != nil {
 			term.Write([]byte(fmt.Sprintln("Error: " + err.Error())))
 			continue
 		}
-		term.Write([]byte(fmt.Sprintln(strconv.FormatFloat(res, 'G', -1, 64))))
+
+		switch format {
+		case "H":
+			term.Write([]byte(fmt.Sprintf("0x%02X\n", int(res))))
+		default:
+			term.Write([]byte(fmt.Sprintln(strconv.FormatFloat(res, format[0], -1, 64))))
+		}
+
 	}
 }
 

operators/functions/abs.go

@@ -5,7 +5,7 @@ import (
 )
 
 import (
-	"github.com/alfredxing/calc/operators"
+	"github.com/denysvitali/calc/operators"
 )
 
 var (

operators/functions/functions.go

@@ -1,7 +1,7 @@
 package functions
 
 import (
-	"github.com/alfredxing/calc/operators"
+	"github.com/denysvitali/calc/operators"
 )
 
 var Names = map[string]bool{}

operators/functions/log.go

@@ -5,7 +5,7 @@ import (
 )
 
 import (
-	"github.com/alfredxing/calc/operators"
+	"github.com/denysvitali/calc/operators"
 )
 
 var (

operators/functions/sqrt.go

@@ -5,7 +5,7 @@ import (
 )
 
 import (
-	"github.com/alfredxing/calc/operators"
+	"github.com/denysvitali/calc/operators"
 )
 
 var (

operators/functions/trig.go

@@ -5,7 +5,7 @@ import (
 )
 
 import (
-	"github.com/alfredxing/calc/operators"
+	"github.com/denysvitali/calc/operators"
 )
 
 var (