BE

A BASH-powered extendable template engine.

Why? Because I felt like it! Plus, I needed something for my blog which is also powered by BASH.

It is nothing fancy, but it does the job.

Example

#!/bin/bash

. ./be

be_bold() {
  local input
  input=$(cat -)
  echo "<strong>${input}</strong>"
}

be_replace() {
  local input
  input=$(cat -)
  echo "${input//$1/$2}"
}

be_capitalize() {
  local input
  input=$(cat -)
  echo "${input^}"
}

be_equals() {
  local block
  block=$(cat -)

  if [[ "$1" == "$2" ]]; then
    be <<< "$block"
  else
    # Failed, return nothing.
    echo ""
  fi
}

NAME="Joe"
LIKES="hockey,soccer"
TPL=$(cat <<EOF
  Well, well, hello {{NAME|APPEND e|APPEND e}}!
  {{@ASSIGN GOODBYE}}Goodbye, {{NAME|CAPITALIZE}}!{{/ASSIGN GOODBYE}}
  {{#LIKES}}
    So {{NAME|REPLACE "e" "ey"|BOLD}}, I heard you like:
    {{@FOREACH LIKES ,}}
      {{@ASSIGN IS_HOCKEY}}{{@EQUALS VALUE "hockey"}}true{{/EQUALS VALUE "hockey"}}{{/ASSIGN IS_HOCKEY}}
      {{KEY1}}) {{VALUE|CAPITALIZE}}{{#IS_HOCKEY}} (love!){{/IS_HOCKEY}}{{^LAST}}; and {{/LAST}}
    {{/FOREACH LIKES ,}}
    {{@RAW}}Won't be processed: {{NAME}}{{/RAW}}
  {{/LIKES}}
  {{GOODBYE}}
EOF
)

echo "$TPL" | be

Output:

  Well, well, hello Joeee!
  
  
    So <strong>Joey</strong>, I heard you like:
    
      
      1) Hockey (love!); and 
    
      
      2) Soccer
    
    Won't be processed: {{NAME}}

Built-ins

Varaibles

{{VAR}}

Will replace with the value of VAR.

Piping: {{VAR|UPPERCASE|REPLACE X Y}}

Will replace VAR with the value of VAR, then run it through a custom function UPPERCASE, then run it througha custom function REPLACE where it has the arguments of X and Y (replace X with Y).

Supports for quoting as well:

• {{VAR|UPPERCASE|REPLACE "X" "Y"}}; or
• {{VAR|UPPERCASE|REPLACE "\"" "'"}}

If

{{#VAR}}Works!{{/VAR}}

Will show Works! if VAR is defined.

Unless

{{^VAR}}Works!{{/VAR}}

Will only show Works! if VAR is not defined.

Foreach

{{@FOREACH VAR DEL}}{{KEY}}:{{VALUE}}{{^LAST}}, {{/LAST}}{{/FOREACH VAR DEL}}

Will accept a variable to loop VAR with optional delimiter DEL. If DEL is not provided, it will simply loop by space.

The following special variables are usable inside a loop:

• KEY - Current key index
• KEY0 - Current key index, zero-based
• KEY1 - Current key index + 1
• VALUE - Value for current key
• FIRST - If this is the first iteration
• LAST - If this is the last iteration

Partials

{{>templates/_partial}}

Will include and process the file templates/_partial.

Raw

{{@RAW}}Will be skipped {{NAME}}{{/RAW}}

Will skip over anything defined inside.

Assignments

{{@ASSIGN HELLO}}Hello! {{NAME|CAPITALIZE}}{{/ASSIGN HELLO}}

Then, use {{HELLO}} to display.

Custom functions

Simply define your own function with a prefix of be_. The subject and arguments will be passed in to work with.

The subject is subjective to the type. If it is a block, then the subject is the block content. If it is a pipe in a variable, then the subject is the parsed variable (thus far).

# Pipe example.
be_bold() {
  local input
  input=$(cat -)
  echo "<strong>${input}</strong>"
}

NAME="Joe"
echo "{{NAME|BOLD}}" | be
# Output: "<strong>Joe</strong>"

# Pipe example #2.
be_bold() {
  local input
  input=$(cat -)
  echo "<$1>${input}</$1>"
}

NAME="Joe"
echo "{{NAME|BOLD em}}" | be
# Output: "<em>Joe</em>"

# Function example.
be_bold() {
  local input
  input=$(cat -)
  echo "<strong>${input}</strong>"
}

NAME="Joe"
echo "{{@BOLD}}{{NAME}}{{/BOLD}}" | be
# Output: "<strong>Joe</strong>"

LICENSE

This project is released under the MIT license.