Require "big" if requiring any "big" file

src/big/big_decimal.cr

@@ -1,3 +1,5 @@
+require "big"
+
 # A `BigDecimal` represents arbitrary precision decimals.
 #
 # It is internally represented by a pair of `BigInt` and `UInt64`: value and scale.

src/big/big_float.cr

@@ -1,4 +1,5 @@
 require "c/string"
+require "big"
 
 # A `BigFloat` can represent arbitrarily large floats.
 #

src/big/big_int.cr

@@ -1,4 +1,5 @@
 require "c/string"
+require "big"
 
 # A `BigInt` can represent arbitrarily large integers.
 #

src/big/big_rational.cr

@@ -1,3 +1,5 @@
+require "big"
+
 # Rational numbers are represented as the quotient of arbitrarily large
 # numerators and denominators. Rationals are canonicalized such that the
 # denominator and the numerator have no common factors, and that the