compat: Add Mes shims for the 'eval' module.

* gash/compat.scm [mes] (string-concatenate-reverse): New procedure.
[mes] (char-pred): New procedure.
[mes] (string-any): New procedure.
[mes] (string-every): Allow character sets and characters as the
predicated (using 'char-pred').

gash/compat.scm

@@ -18,6 +18,7 @@
 
 (define-module (gash compat)
   #:use-module (ice-9 match)
+  #:use-module (srfi srfi-14)
   #:export (if-guile-version-below
             when-mes))
 
@@ -85,7 +86,9 @@
           make-parameter
           parameterize
           set-port-line!
+          string-concatenate-reverse
           string-every
+          string-any
           the-eof-object
           noop
           make-prompt-tag
@@ -123,8 +126,21 @@
   (define (set-port-line! port line)
     #f)
 
+  (define (string-concatenate-reverse lst)
+    (apply string-append (reverse lst)))
+
+  (define (char-pred pred)
+    (cond
+     ((char? pred) (lambda (x) (char=? x pred)))
+     ((char-set? pred) (lambda (x) (char-set-contains? pred x)))
+     ((procedure? pred) pred)
+     (else (error "Invalid character predicate."))))
+
   (define (string-every pred str)
-    ((@ (srfi srfi-1) every) pred (string->list str)))
+    ((@ (srfi srfi-1) every) (char-pred pred) (string->list str)))
+
+  (define (string-any pred str)
+    ((@ (srfi srfi-1) any) (char-pred pred) (string->list str)))
 
   (define the-eof-object (integer->char -1))