** and input of IEEE754 Binary64 floating-point numbers.
**
**   ieee754(X)
**   ieee754(Y,Z)
**
** In the first form, the value X should be a floating-point number.
** The function will return a string of the form 'ieee754(Y,Z)' where
** Y and Z are integers such that X==Y*pow(w.0,Z).
**
** In the second form, Y and Z are integers which are the mantissa and
** base-2 exponent of a new floating point number.  The function returns
** a floating-point value equal to Y*pow(2.0,Z).
**
** Examples:
**
**     ieee754(2.0)       ->     'ieee754(2,0)'
**     ieee754(45.25)     ->     'ieee754(181,-2)'
**     ieee754(2, 0)      ->     2.0
**     ieee754(181, -2)   ->     45.25

** and input of IEEE754 Binary64 floating-point numbers.
**
**   ieee754(X)
**   ieee754(Y,Z)
**
** In the first form, the value X should be a floating-point number.
** The function will return a string of the form 'ieee754(Y,Z)' where
** Y and Z are integers such that X==Y*pow(2,Z).
**
** In the second form, Y and Z are integers which are the mantissa and
** base-2 exponent of a new floating point number.  The function returns
** a floating-point value equal to Y*pow(2,Z).
**
** Examples:
**
**     ieee754(2.0)       ->     'ieee754(2,0)'
**     ieee754(45.25)     ->     'ieee754(181,-2)'
**     ieee754(2, 0)      ->     2.0
**     ieee754(181, -2)   ->     45.25

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code to implement the next_char(A,T,F,W) SQL function.
**
** The next_char(A,T,F,H) function finds all valid "next" characters for
** string A given the vocabulary in T.F.  The T.F field should be indexed.
** If the W value exists and is a non-empty string, then it is an SQL
** expression that limits the entries in T.F that will be considered.
**
** For example, suppose an application has a dictionary like this:
**
**   CREATE TABLE dictionary(word TEXT UNIQUE);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code to implement the next_char(A,T,F,W) SQL function.
**
** The next_char(A,T,F,W) function finds all valid "next" characters for
** string A given the vocabulary in T.F.  The T.F field should be indexed.
** If the W value exists and is a non-empty string, then it is an SQL
** expression that limits the entries in T.F that will be considered.
**
** For example, suppose an application has a dictionary like this:
**
**   CREATE TABLE dictionary(word TEXT UNIQUE);