Term "expression" is more popular than "formula"

Author: avsej

contextual.textile

@@ -1411,7 +1411,7 @@ First meekly ` yylex () `-<code >'('` look at the section.
 
 
 
-The first ` if ` is ` tLPAREN ` So the usual formula in parentheses. The criterion is ` lex_state ` is
+The first ` if ` is ` tLPAREN ` So the usual expression in parentheses. The criterion is ` lex_state ` is
 ` BEG ` or ` MID `, that is absolutely the beginning when the ceremony.
 
 
@@ -1451,7 +1451,7 @@ args: arg
 
 arg: primary
 
-primary: tLPAREN compstmt ')' / * * usual formula parentheses /
+primary: tLPAREN compstmt ')' / * * usual expression parentheses /
               | TLPAREN_ARG expr ')' / * parenthetical first argument * /
               | Method_call
 </pre>

intro.textile

@@ -246,7 +246,7 @@ It's sometimes corresponds to crucial importance, sometimes it doesn't matter
 practically. Yet, this is certainly an appealing point if a language seeks for
 "handy and easy", and Ruby does. 
 
-h4. Most of syntactic elements are formulae
+h4. Most of syntactic elements are expressions
 
 This topic is probably difficult to understand it instantly without needs
 supplemental explanation.  For example, the following C-language program
@@ -263,10 +263,10 @@ result = cond ? process(val) : 0;
 </pre>
 
 This rewrite is possible because the conditional operator (@a?b:c@) is defined
-as a formula. 
+as an expression.
 
 
-On the other hand, Ruby acceps a following expression because @if@ is a formula. 
+On the other hand, Ruby acceps a following expression because @if@ is an expression.
 
 p(=emlist). 
 result = if cond then process(val) else nil end