# Coerce with Rational and Complex

**URL:** <https://www.ruby-forum.com/t/coerce-with-rational-and-complex/135358>\
**Category:** Development\
**Created:** [April 21, 2008, 2:56pm UTC](https://www.ruby-forum.com/t/coerce-with-rational-and-complex/135358 "2008-04-21T14:56:51Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Yusuke\_ENDOH](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/c89c15/32.png) [@Yusuke\_ENDOH](https://www.ruby-forum.com/u/Yusuke_ENDOH)\
**Post date:** [April 21, 2008, 2:56pm UTC](https://www.ruby-forum.com/t/coerce-with-rational-and-complex/135358/1 "2008-04-21T14:56:51Z")

</div>

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```
p 1.coerce(Rational(1, 2)) #=> [0.5, 1.0]

```

e$BD\>46E\*$K$Oe(B [Rational(1, 2), Rational(1, 1)] e$B$,M\_$7$$$G$9!#e(B  
e$B$^$?!"0J2\<$O$I$&$G$7$g$&$+!#e(B

```
p 1.coerce(Complex(1, 1)) #=> can't convert 1+1i into Integer

```

[Complex(1, 0), Complex(1, 1)] e$B$,M\_$7$$5$J,$G$9!#e(B

e$B$3$d$D$i$,AH$_9~$_$K$J$C$?;v$G!“e(Bcoerce e$B$r$$$m$$$m$H9M$(D\>$9e(B  
e$BI,MW$,$”$k$N$+$b$7$l$^$;$s!#e(B

---

<div class="post-metadata">

**Author:** ![Yusuke\_ENDOH](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/c89c15/32.png) [@Yusuke\_ENDOH](https://www.ruby-forum.com/u/Yusuke_ENDOH)\
**Post date:** [April 22, 2008, 12:00pm UTC](https://www.ruby-forum.com/t/coerce-with-rational-and-complex/135358/2 "2008-04-22T12:00:10Z")

</div>

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> [Complex(1, 0), Complex(1, 1)] e$B$,M\_$7$$5$J,$G$9!#e(B

e$B86B’$H$7$F!"e(Bcoerce  
e$B$O!"e(B(e$B?7$7$$?te(B).coerce(e$B8E$$?t!K$N$\_$,LdBj$J$N$G!"e(B  
1.coerce(Rational(1,2))  
e$B$N$h$&$J!"e(B(e$B8E$$?te(B).coerce(e$B?7$7$$?t!K$H$$$&e(B  
e$B%Q%?!\<%s$G$O5/F0$7$J$$$O$:$G$9!#$@$+$i!"JQ$JCM$rJV$7$F$b!“Nc30$G$b$+$^e(B  
e$B$o$J$$$G$9!#$b$A$m$s!”$=$l$C$]$$CM$rJV$7$F$b32$O$J$$$G$9$,!#$$$d!"5,Lse(B  
e$B$rGK$C$?$7$k$7$KNc30$r=P$7$?J}$,$+$($C$F$$$$$+$J!#e(B

---

<div class="post-metadata">

**Author:** ![Yusuke\_ENDOH](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/y/c89c15/32.png) [@Yusuke\_ENDOH](https://www.ruby-forum.com/u/Yusuke_ENDOH)\
**Post date:** [April 22, 2008, 4:31pm UTC](https://www.ruby-forum.com/t/coerce-with-rational-and-complex/135358/3 "2008-04-22T16:31:49Z")

</div>

e$B1sF#$G$9!#e(B

08/04/22 e$B$Ke(B Shin-ichiro HARA[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
e$B$5$s$O=q$-$^$7$?e(B:

> > ```
> > p 1.coerce(Complex(1, 1)) #=> can't convert 1+1i into Integer
> > 
> > ```
> > 
> > [Complex(1, 0), Complex(1, 1)] e$B$,M\_$7$$5$J,$G$9!#e(B
> 
> e$B86B’$H$7$F!"e(Bcoerce e$B$O!"e(B(e$B?7$7$$?te(B).coerce(e$B8E$$?t!K$N$\_$,LdBj$J$N$G!"e(B  
> 1.coerce(Rational(1,2)) e$B$N$h$&$J!"e(B(e$B8E$$?te(B).coerce(e$B?7$7$$?t!K$H$$$&e(B  
> e$B%Q%?!\<%s$G$O5/F0$7$J$$$O$:$G$9!#$@$+$i!"JQ$JCM$rJV$7$F$b!“Nc30$G$b$+$^e(B  
> e$B$o$J$$$G$9!#$b$A$m$s!”$=$l$C$]$$CM$rJV$7$F$b32$O$J$$$G$9$,!#$$$d!"5,Lse(B  
> e$B$rGK$C$?$7$k$7$KNc30$r=P$7$?J}$,$+$($C$F$$$$$+$J!#e(B

e$B$J$k$[$I!"$=$&$$$&@\_7W$J$s$G$9$M!#$J$s$H$J$/$o$+$j$^$7$?!#e(B

e$B0l1~$=$l$C$]$$CM$rJV$9%Q%C%A$r$$$$2C8:$K=q$$$F$\_$^$7$?!#e(B

# Index: numeric.c

— numeric.c (revision 16157)  
+++ numeric.c (working copy)  
@@ -97,6 +97,8 @@  
}

+static int do\_coerce(VALUE \*x, VALUE _y, int err);  
+  
/_

- call-seq:
- 

```
num.coerce(numeric) => array

```

@@ -116,9 +118,14 @@  
static VALUE  
num\_coerce(VALUE x, VALUE y)  
{

- static int recurse = 0;  
if (CLASS\_OF(x) == CLASS\_OF(y))  
return rb\_assoc\_new(y, x);

- return rb\_assoc\_new(rb\_Float(y), rb\_Float(x));

- if (recurse) return Qnil;
- recurse++;
- do\_coerce(&x, &y, Qtrue);
- recurse–;
- return rb\_assoc\_new(y, x);  
}

static VALUE