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* Conditionals.

This commit is contained in:
Eelco Dolstra 2003-08-05 13:05:30 +00:00
parent b9c9b461ea
commit d34b4d4f28
1 changed files with 33 additions and 0 deletions
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33
src/fix.cc
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@ -146,6 +146,8 @@ static Expr evalExpr2(EvalState & state, Expr e)
/* Normal forms. */
if (ATmatch(e, "<str>", &s1) ||
ATmatch(e, "[<list>]", &e1) ||
ATmatch(e, "True") ||
ATmatch(e, "False") ||
ATmatch(e, "Function([<list>], <term>)", &e1, &e2) ||
ATmatch(e, "FSId(<str>)", &s1))
return e;
@ -167,6 +169,37 @@ static Expr evalExpr2(EvalState & state, Expr e)
substExprMany((ATermList) e3, (ATermList) e2, e4));
}
/* Conditional. */
if (ATmatch(e, "If(<term>, <term>, <term>)", &e1, &e2, &e3)) {
e1 = evalExpr(state, e1);
Expr x;
if (ATmatch(e1, "True")) x = e2;
else if (ATmatch(e1, "False")) x = e3;
else throw badTerm("expecting a boolean", e1);
return evalExpr(state, x);
}
/* Ad-hoc function for string matching. */
if (ATmatch(e, "HasSubstr(<term>, <term>)", &e1, &e2)) {
e1 = evalExpr(state, e1);
e2 = evalExpr(state, e2);
char * s1, * s2;
if (!ATmatch(e1, "<str>", &s1))
throw badTerm("expecting a string", e1);
if (!ATmatch(e2, "<str>", &s2))
throw badTerm("expecting a string", e2);
return
string(s1).find(string(s2)) != string::npos ?
ATmake("True") : ATmake("False");
}
/* Platform constant. */
if (ATmatch(e, "Platform")) {
return ATmake("<str>", SYSTEM);
}
/* Fix inclusion. */
if (ATmatch(e, "IncludeFix(<str>)", &s1)) {
string fileName(s1);