.pgaw:Help.f.t insert end \
"PostgreSQL functions" {title} \
"

Many data types have functions available for conversion to other related types. In addition, there are some type-specific functions. Some functions are also available through operators and may be documented as operators only. 

" {} \
"\tSQL functions\n" {link sqlfunc} \
"\tMathematical functions\n" {link mathfunc} \
"\tString functions\n" {link stringfunc} \
"\tDate/Time functions\n" {link datefunc} \
"\tGeometric functions\n" {link geomfunc} \
"\tIP V4 functions" {link ipv4func}