Merge pull request #3 from Syuparn/add-file-options

Add file options

README.md

@@ -7,6 +7,12 @@ executable go-template command (like awk and jq!)
 $ go get -u github.com/syuparn/tmplscript
 $ echo "hello" | tmplscript '{{print . ", " "world!"}}'
 hello, world!
+# read from file instead
+$ seq 15 | tmplscript -f example/fizzbuzz.tmpl
+1
+2
+fizz
+...
 ```
 
 REPL mode

example/fizzbuzz.tmpl

@@ -0,0 +1,5 @@
+{{- with $i := int . -}}
+    {{- $fizz := mod $i 3 | eq 0 | ternary "fizz" "" -}}
+    {{- $buzz := mod $i 5 | eq 0 | ternary "buzz" "" -}}
+    {{- coalesce (print $fizz $buzz) $i -}}{{- "\n" -}}
+{{- end -}}

example/template_as_func.tmpl

@@ -0,0 +1,9 @@
+{{- define "templateAdd" -}}
+    {{- /* HACK: assign dummy var to be evaluated as "" */ -}}
+    {{- $_ := set . "ret" (add (index .args 0) (index .args 1)) -}}
+{{- end -}}
+
+{{- with $d := dict "args" (list 2 3) -}}
+    {{- template "templateAdd" $d -}}
+    {{- print "result: " $d.ret -}}
+{{- end -}}

example/template_factorial.tmpl

@@ -0,0 +1,32 @@
+{{- define "_fact" -}}
+    {{- $i := index . 0 -}}
+    {{- $acc := index . 1 -}}
+    {{- if le $i 1 -}}
+        {{- println $acc -}}
+    {{- else -}}
+        {{- template "_fact" list (sub $i 1) (mul $acc $i) -}}
+    {{- end -}}
+{{- end -}}
+
+{{- define "fact" -}}
+    {{- template "_fact" list . 1 -}}
+{{- end -}}
+
+
+{{- range $i := until 11}}
+    {{- printf "%2d! = " $i}}{{template "fact" $i}}
+{{- end}}
+
+{{- /*
+ 0! = 1
+ 1! = 1
+ 2! = 2
+ 3! = 6
+ 4! = 24
+ 5! = 120
+ 6! = 720
+ 7! = 5040
+ 8! = 40320
+ 9! = 362880
+10! = 3628800
+*/ -}}

main.go

@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"flag"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"reflect"
 	"strings"
@@ -14,6 +15,7 @@ import (
 )
 
 var (
+	fileName = flag.String("f", "", "use template file")
 	runsREPL = flag.Bool("i", false, "run interactive REPL instead")
 )
 
@@ -25,6 +27,22 @@ func main() {
 		return
 	}
 
+	if *fileName != "" {
+		fp, err := os.Open(*fileName)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "failed to open %s: %v\n", *fileName, err)
+			return
+		}
+
+		b, err := ioutil.ReadAll(fp)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "failed to read %s: %v\n", *fileName, err)
+		}
+
+		runPipeMode(string(b))
+		return
+	}
+
 	if flag.Arg(0) == "" {
 		fmt.Fprintf(os.Stderr, "template must be passed to argument\n")
 		return