added strutils.align

1 files changed, 23 insertions, 3 deletions

diff --git a/lib/pure/strutils.nim b/lib/pure/strutils.nim
index f5adf1abb..81ca75417 100755
--- a/lib/pure/strutils.nim
+++ b/lib/pure/strutils.nim
@@ -449,8 +449,20 @@ proc repeatChar*(count: int, c: Char = ' '): string {.noSideEffect,
   ## Returns a string of length `count` consisting only of

   ## the character `c`.

   result = newString(count)

-  for i in 0..count-1:

-    result[i] = c

+  for i in 0..count-1: result[i] = c

+

+proc align*(s: string, count: int): string {.

+  noSideEffect, rtl, extern: "nsuAlignString".} =

+  ## Aligns a string `s` with spaces, so that is of length `count`. Spaces are

+  ## added before `s` resulting in right alignment. If ``s.len >= count``, no

+  ## spaces are added and `s` is returned unchanged.

+  if s.len < count: 

+    result = newString(count)

+    var spaces = count - s.len

+    for i in 0..spaces-1: result[i] = ' '

+    for i in spaces..count-1: result[i] = s[i-spaces]

+  else:

+    result = s

 

 proc startsWith*(s, prefix: string): bool {.noSideEffect,

   rtl, extern: "nsuStartsWith".} =

@@ -739,7 +751,7 @@ proc validEmailAddress*(s: string): bool {.noSideEffect,
   rtl, extern: "nsuValidEmailAddress".} = 

   ## returns true if `s` seems to be a valid e-mail address. 

   ## The checking also uses a domain list.

-  ## Note: This will be moved into another module soon.

+  ## Note: This will be moved to another module soon.

   const

     chars = Letters + Digits + {'!','#','$','%','&',

       '\'','*','+','/','=','?','^','_','`','{','}','|','~','-','.'}

@@ -862,3 +874,11 @@ proc editDistance*(a, b: string): int {.noSideEffect,
   #dealloc(row)

 

 {.pop.}

+

+when isMainModule:

+  assert align("abc", 4) == " abc"

+  assert align("a", 0) == "a"

+  assert align("1232", 6) == "  1232"

+

+  

+