Merge pull request #6 from PESchoenberg/develop

Develop

README.md

@@ -10,7 +10,7 @@ Some useful functions for GNU Guile Scheme programs.
 
 ## Dependencies:
 
-* GNU Guile - ver 2.0. or newer ( https://www.gnu.org/software/guile/ )
+* GNU Guile - ver 2.2.3 or newer ( https://www.gnu.org/software/guile/ )
 
 
 ## Installation:
@@ -22,16 +22,16 @@ into a folder of your choice and cd into it.
 details concerning your OS and distribution, but as an example, on Ubuntu you
 would issue:
 
-      sudo mkdir /usr/share/guile/site/2.0/grsp
+      sudo mkdir /usr/share/guile/site/2.2/grsp
 
-      sudo cp *.scm -rv /usr/share/guile/site/2.0/grsp
+      sudo cp *.scm -rv /usr/share/guile/site/2.2/grsp
 
 and that will do the trick.
 
 
 ## Uninstall:
 
-* You just need to remove /usr/share/guile/site/2.0/grsp and its subfolders.
+* You just need to remove /usr/share/guile/site/2.2/grsp and its subfolders.
 
 * There are no other dependencies.
 

examples/example1.scm

@@ -101,7 +101,51 @@
 (display res)
 (newlines 1)
 
-
-
-
+; Environment (interpreter ) version analysis.
+(ptit " " 1 1 "6 - Version:")
+(newline)
+(display "Your current GNU Guile version is ")
+(display (version))
+(display " and your current effective version is ")
+(display (effective-version))
+(newlines 2)
+
+(define ver 1.8)
+(display (strings-append (list "Regarding effective version " (number->string ver) " your Scheme effective version is: ") 0))
+(newline)
+(display "Lower? ")
+(display (grsp-lang-effective-version "lt" ver))
+(newline)
+(display "Equal? ")
+(display (grsp-lang-effective-version "eq" ver))
+(newline)
+(display "Higher? ")
+(display (grsp-lang-effective-version "ht" ver))
+(newlines 2)
+
+(set! ver 2.0)
+(display (strings-append (list "Regarding version " (number->string ver) " your Scheme version is: ") 0))
+(newline)
+(display "Lower? ")
+(display (grsp-lang-effective-version "lt" ver))
+(newline)
+(display "Equal? ")
+(display (grsp-lang-effective-version "eq" ver))
+(newline)
+(display "Higher? ")
+(display (grsp-lang-effective-version "ht" ver))
+(newlines 2)
+
+(set! ver 2.2)
+(display (strings-append (list "Regarding version " (number->string ver) " your Guile Scheme version is: ") 0))
+(newline)
+(display "Lower? ")
+(display (grsp-lang-effective-version "lt" ver))
+(newline)
+(display "Equal? ")
+(display (grsp-lang-effective-version "eq" ver))
+(newline)
+(display "Higher? ")
+(display (grsp-lang-effective-version "ht" ver))
+(newlines 2)
 

grsp0.scm

@@ -32,7 +32,8 @@
 	    pres
 	    newspaces
 	    strings-append
-	    read-file-as-string))
+	    read-file-as-string
+	    grsp-lang-effective-version))
 
 
 ; pline - displays character p_n p_m times in one line at the console.
@@ -50,7 +51,7 @@
 	         (loop (+ i 1)))))))
 
 
-; ptit - displays a console title surrounded by one or two lines.
+; ptit - displays a console title with one or two lines.
 ;
 ; Arguments:
 ; - p_c: line character to display.
@@ -144,7 +145,7 @@
 ; read-file-as-string - reads a file as a string; adapted from an example 
 ; from sources indicated below. The string will be formatted and include 
 ; characters such as \n and \r. What this does in practice is to read a 
-; file and return it as one single string.
+; file and return it as one single string. 
 ;
 ; Arguments:
 ; - p_f: file name.
@@ -163,5 +164,23 @@
 	    (loop (cons c ls1) (read-char p)))))))
 
 
-
-
+; Checks if currently instaled GNU Guile's effective version is less, equal or 
+; higher than value of the version argument vakue.
+;
+; Arguments:
+; - p_s: enter the one of the following strings.
+;   - "lt" less than.
+;   - "eq" equal to.
+;   - "ht" higher than.
+; - p_v: version number to check against.
+;
+; Output:
+; - Boolean. Defaults to #f if p_s is entered incorrectly.
+;
+(define (grsp-lang-effective-version p_s p_v)
+  (let ((res #f)
+	(ev (string->number (effective-version))))
+    (if (equal? p_s "lt")(set! res (< ev p_v)))
+    (if (equal? p_s "eq")(set! res (= ev p_v)))
+    (if (equal? p_s "ht")(set! res (> ev p_v)))
+    res))