Preserving whitespace prefix in multiline strings #178
Description
In the StringTemplate engine - which I've used in some projects to emit C code - whitespace prefixes are automatically added in the output lines:
PrintCFunction(linesGlobal, linesLocal) ::= <<
void foo() {
if (someRuntimeFlag) {
<linesGlobal>
if (anotherRuntimeFlag) {
<linesLocal>
}
}
}
>>
When this template is rendered in StringTemplate, the whitespace prefixing the multilined linesGlobal and linesLocal strings, is copied for all the lines emitted. The generated C code is e.g.:
void foo() {
if (someRuntimeFlag) {
int i;
i=1; // <=== whitespace prefix copied in 2nd
i++; // <=== and 3rd line
if (anotherRuntimeFlag) {
int j=i;
j++; // <=== ditto
}
}
}
I am new to Jinja2 - and tried to replicate this:
#!/usr/bin/env python
from jinja2 import Template
linesGlobal='\n'.join(['int i;', 'i=1;'])
linesLocal='\n'.join(['int j=i;', 'j++;'])
tmpl = Template(u'''\
void foo() {
if (someRuntimeFlag) {
{{linesGlobal}}
if (anotherRuntimeFlag) {
{{linesLocal}}
}
}
}
''')
print tmpl.render(
linesGlobal=linesGlobal,
linesLocal=linesLocal)
...but saw it produce this:
void foo() {
if (someRuntimeFlag) {
int i;
i=1;
if (anotherRuntimeFlag) {
int j=i;
j++;
}
}
}
...which is not what I want. I managed to make the output emit proper whitespace prefixes with this:
...
if (someRuntimeFlag) {
{{linesGlobal|indent(8)}}
if (anotherRuntimeFlag) {
{{linesLocal|indent(12)}}
}
}
...but this is arguably bad, since I need to manually count whitespace for every string I emit...
Is there a better way that I am missing?