TextMate:Create Snippet

1. -plain text: just insert text
   
2. -variables: $TM_SELECTED_TEXT
   
3. -variables with default: ${TM_SELECTED_TEXT:default text}
   
4. -variables with regexp: ${TM_SELECTED_TEXT/regexp/format/options}
   
5.   ex. ${TM_SELECTED_TEXT/w+/<$0>/g}
   
6. -Shell Code Insertion: ex. <a href="`pbpaste`">$TM_SELECTED_TEXT</a>
   
7. -Tab Stops: $0 or $1..$n
   
8. -Tab Stops with Default(Placeholders): ${1:default}
   
9. -Mirrors: ex. <${1:div}>  $0  </$1>
   
10. -Transformations: ${1/regexp/format/options}
    
11. -Transformations with condition: ${1/x$|(.+)/(?1:other)/}
    
12. -Cascading placeholders: ${1:default${2:default}}